Beautiful, I totally agree with that.

Except that we can always take it one step further: providing capabilities the user is not even expecting that would be possible in order to make their experience easier and more direct. Take the Gmail's auto-complete-fields-from-contact-list-addresses as an example.

Rui Ramos

Robert - no holes to shoot in that argument. Actually, when I was asked in an interview about what I found most important in an interface, I answered with that same word - predictability.

-Todd

On Sat, May 24, 2008 at 8:54 PM, Robert Hoekman Jr robert at rhjr.net wrote:

"Usability equals predictability." As in, if you can accurately predict what's going to happen next in an interaction, it's because the action you're taking is understandable, clear, logical, makes you feel confident, etc. If you can accurately predict what's next, the interaction has high usability. If you can't accurately predict what's next, the interaction has low usability. Shoot holes in that statement. -r-

One could argue that — given a context — "disruption" can actually be good: if things are too predictable, sudden changes of patterns can grab people's attention back.

I remember watching this interview by Bruce Sterling ( http://www.technologyreview.com/video/design ) when his talking about design... the interview all brilliant, but the piece I wanted to brought up was this:

"I went down once into the accelerator in cern in geneva. and when we were driving around the accelerator ring in an electric golf cart and the guy was explaining that they are out, you know, pursuing the pi meson or whatever, he said, you know quite often we have accidents down here because, people are driving the 27km line of this tube and they just zone out and crash into the wall, so I said why don't you just put in some murals to break the visual monotony, and he just starred like I had come from mars, and I said look, its lit 24 hours right, why don't you put in some house plants, I mean just kind of humanize the interface a little bit, I mean this is so punishingly monotonous that you are actually harming people. the guy's brain couldn't go there, its a physics instrument, you can't paint it!%u201D

Ok, putting in simple words "If predictability (when is NOT monotony!) = Usability!

{ Itamar Medeiros } Information Designer
http://designative.info/
http://www.autodesk.com/

Posted from the new ixda.org
http://www.ixda.org/discuss?post=29451

Predictability, "works", and "meets a real current human need" is best of all.

Seems to me that "works" is enveloped by the idea of attaining an expected result. If it didn't work, you wouldn't get what you expected.

And "meets a real current human need" relates to the value proposition, not whether or not someone can use it or the degree to which it is usable.

(By the way, the game is: you attack, and I deflect.) : 

-r-

Predictability is one important attribute of usability for most products; however, if you are a game designer, then unpredictability is important for posing gamers with some challenge.

Chauncey

On Sat, May 24, 2008 at 10:09 PM, Rui Miguel Ramos ruiramos at gmail.com wrote: Beautiful, I totally agree with that. Except that we can always take it one step further: providing capabilities the user is not even expecting that would be possible in order to make their experience easier and more direct. Take the Gmail's auto-complete-fields-from-contact-list-addresses as an example. Rui Ramos Welcome to the Interaction Design Association (IxDA) ! To post to this list . discuss at ixda.org Unsubscribe .... http://www.ixda.org/unsubscribe List Guidelines http://www.ixda.org/guidelines List Help http://www.ixda.org/help

"Usability equals predictability."

Not everything that's usable is predictable and not everything that's predictable is usable.

-- Kontra
http://counternotions.com

Predictability is one important attribute of usability for most products; however, if you are a game designer, then unpredictability is important for posing gamers with some challenge.

We may be talking about 2 different things, though. If you're playing a video game and you shoot a guy in the chest and he dies a dramatic death and hands a grenade to another bad guy before falling 12 floors to his last breath, that would be an unpredictable event, and would certainly add to the enjoyability and challenge of the game.

If, on the other hand, nothing happened after shooting him in the chest, well, that would be a usability issue.

Eh?

-r-

Not everything that's usable is predictable and not everything that's predictable is usable.

Examples?

-r-

One could argue that — given a context — "disruption" can actually be good: if things are too predictable, sudden changes of patterns can grab people's attention back.

Fantastic point! Let's see where it takes us (thinking out loud now) ...

So, under what circumstances do we need to grab their attention back? I suppose a system error could be a good reason. I doubt many people expect or desire system errors.

But if there's a system error, isn't that a usability issue? As in, if a system error occurs when I was expecting something else, then doesn't that mean the system is less usable than it should be? Is system reliability is part of usability? (Seems so, but are there arguments that this is not the case?)

In Bruce Sterling's example, the lack of scenery caused people to daze out and crash, presumably because the scenery was too predictable. Leading people to crash would be a definite usability issue, I'd say. And in that case, predictability seemed to cause it. Unpredictability — in this case, some texture in the design — could have prevented lots of crashes.

However, one could argue that the golf cart driver's prediction should be being able to get through the 27km line of tube without crashing. "I predict I will get through this unharmed" seems like a perfectly reasonable statement to make. How hard is it to drive a golf cart, after all?

Hmm.

Thoughts? There's definitely something to your argument, and I'd like to explore it more.

-r-

One example would be someone who has never used a computer before, let's say a small child around the age of 4.
Let's say it's an iPhone to be specific.

I would not use the term 'predictable', even though the interface is very usable.

I would use the term 'intuitive'.

On May 24, 2008, at 10:25 PM, Robert Hoekman Jr wrote:

Not everything that's usable is predictable and not everything that's predictable is usable. Examples?

Hi Robert, this equation/statement is faultless. It's good, however, to remind ourselves of it from time-to-time. Often we get carried away and wonder off on a tangent. I see this statement as a 're-set' function for all involved in usability.

Posted from the new ixda.org
http://www.ixda.org/discuss?post=29451

I'm thinking out loud a bit myself this morning. Pulled a late night work on chapters about the QOC method and the use of cause and effect diagrams in UCD. A key issue here is that we often speak of "usability" as a single thing when it has many different attributes.

This is tricky since usability is a general term and usability has many different attributes or dimensions, with predictability being one of those. Usability or more broadly user experience attributes can interact with one another. For example, in studies of what makes a system usable, response time often bubbles to the top of the list (actually, it is often in the top 3) . You could have a system that everyone can learn easily (initial learning) but poor performance (average response time or variability in response time) might make a system that is usable in one dimension, unusable overall. The ISO definition has effectiveness, efficiency, and satisfaction, the basics, but there are many more dimensions to usability that have been considered since the 1980s based on work by Whiteside, Bennett, Gould, and other early proponents of usability engineering, some that overlap broadly. So in the statement below, you could replace "usable" with any one of a number of dimensions and compare it to predicability and examine relationships among different usability attributes. As Itamar noted, unpredicability can be good in some circumstances and human factors engineers have done a lot research into factors that affect vigilance in sustained-attention tasks. Wylie and Mackie in the late 1980s suggested that a system be injected with artificial signals and then the operators would get feedback on their detection performance.

One of the issues that hinders our fields is that we fail to think of usability in our day-to-day work as have many dimensions with some dimensions being more critical in a particular context than others. The simplest example is a system where some people use a feature once a month while others use it 50 times a day. Many people speak of consistency in a user interface as promoting usability but if you have a bi-modal distribution, you may need two interaction methods to be consistent with the way people work. The principles of being inconsistent to be consistent is a difficult one for many corporations who decree that "all our products will be consistent visually and have only one way to perform a task (which gets into another topic of redundancy which is another good debate) . Grudin published what I think is a classic paper that got into the subtleties of consistency (often considered an attribute of a usable system) and noted that to be consistent with how people work, you might need to design systems that have inconsistencies (as well as multiple ways to do things) . The Grudin paper uses old examples, but the issue is still as strong as ever. For a good read see The Case Against User Interface Consistency by Jonathan Grudin at
http://research.microsoft.com/users /jgrudin /publications /consistency /CACM1989.pdf

This is a good topic since I think that an explicit definition of "usability" is critical to each project that we work one; listing the attributes of usability that are most critical to success of a product (learnability, efficiency, prevention of errors, flexibility, predictability, fun, memorability (critical for systems used infrequently like tax software) satisfaction, performance, ....) . I often hear people referring to "usability" and they are each defining it differently which can create problems throughout the product design and development cycle.

Chauncey

On Sun, May 25, 2008 at 1:25 AM, Robert Hoekman Jr robert at rhjr.net wrote: Not everything that's usable is predictable and not everything that's predictable is usable. Examples? -r- Welcome to the Interaction Design Association (IxDA) ! To post to this list . discuss at ixda.org Unsubscribe .... http://www.ixda.org/unsubscribe List Guidelines http://www.ixda.org/guidelines List Help http://www.ixda.org/help

On 25/5/08 10:54 AM, "Robert Hoekman Jr" robert at rhjr.net wrote:

OK, I'll bite.

"Usability equals predictability."

as in you click a link/button/image on a web page, and you predict that it will ... what? ... load a new page completely replacing the current page, or do some AJAX stuff to update just a part of the page?

"predictability" = no changes from what is current expectations = no evolution of ui standards = we'd be stuck with the usability from the 1980's technology, not what we've got now.

no?

e.

On the value proposition: some people separate "usable" (able to complete a task) and "useful" (able to complete the required task at the required time in the required place).

But that's not the definition of "useful". Useful simply means to be of use, does it not? There is definitely a separation. Something can be usable without being useful, and vice-versa. I can use a wristwatch pretty well, but I have no need for one.

Considering a thing/system/site outside of its context of use (i.e. where it needs to be useful) is responsible for much misery - some bloke I sat and listened to the other day (he looked a lot like you, only older) mentioned a police dispatch/alert system that failed because the users didn't want to be finding the control key while being shot at - go figure : 

I'm not considering a thing outside of its context, just exploring whether or not these two terms are synonyms or not.

I'm not sure what you meant, "looked a lot like you, only older", but I'll assume it wasn't meant negatively.

For the record, something about "usability = predictability" has bothered me since I first saw it written yesterday. I'm playing devil's advocate here to see if it holds up. I don't think it does. I'm relying on the IxDA community to come up with all those crafty arguments that make it fall apart.

I tossed this out to the Twitterverse last night as well. The most practical reply I got? Slot machines. Definitely usable while unpredictable.

The best answer? Women. (Crass, perhaps, but funny. Apologies.)

-r-

"predictability" = no changes from what is current expectations = no evolution of ui standards = we'd be stuck with the usability from the 1980's technology, not what we've got now. no?

No. I simply mean that if you, say, click a link on a web page, predicting that it will land you on the About Us page, and it does indeed land you on that page, then that would be deemed to have a high level of usability.

Likewise, if you click a command link or button—regardless of whether it triggers an Ajax function or loads a new page or whatever—as long as you can predict the result (not the UI result, but the net result), then it's usable. For example, you click a Save button believing it will save whatever you've been working on. It doesn't matter if the resulting success indicator is on another page or the same one, what matters is that you were able to accurately and correctly predict what effect the button would have.

If the interaction is clear and understandable, it doesn't matter if it's an old classic or brand new and revolutionary. The subject line of this thread refers only to whether or not you can predict the outcome.

You can innovate all you want as long as what you design is understandable and the outcome predictable, can you not?

Of course, as we've already seen, not all things must be predictable to be usable, so this is all a moot point now. :  Again, just playing devil's advocate here.

-r-

Things can be predictable without being usable. Any tech writer who has ever had the misfortune to have to write in Word will tell you that it screws up numbered lists. It does this in an annoyingly predictable way. Usable it is not.

Cheers,

Martin Polley

Predictability is in large part a result of past experience. When an interface does something in a new way that makes a task easier or adds value to the result, it is doing something unpredictable and increasing usability. What better way to satisfy a user than to pleasantly surprise them?

Jack

Jack L. Moffett
Interaction Designer
inmedius
412.459.0310 x219
http://www.inmedius.com

There is no good design that is not
based on the understanding of people.

- Stefano Marzano
CEO of Philips Design

This is an intriguing discussion, but I fear "Usability = Predictability" is a bit of an oversimplification. So just to antagonize...

Consider an application with 150 functions. The UI for this application consists of a single screen, with a short sentence describing each function in 6pt text. There is a 8x8 pixel green button next to each sentence. Instructions at the top of the screen say "Click the green button next to the function you wish to perform."

Assume the text completely explains the function so any user can understand it, and when they click the tiny green button they get exactly the function they expect from the description of the function.

This UI strikes me as 100% predictable, but I doubt any of us would consider it usable.

So, it seems to me that as elegant as the original equation is, we might need something more along the lines of

findability + accessibility + predictability = usability

Anybody want to add some more terms to the equation?

I've run user tests where I'll sit someone in front of a screen and before I give them a task, or even let them touch anything, I ask them to predict what each element of the interface will do. Sometimes nuanced problems are picked up this way which might otherwise be missed.

I'm guessing this is a pretty common thing to do in user testing (standard practice even? I'm emphatically not an expert...). Either way, I've found it useful. And it's based on the assumption - correct I think - that a big chunk of usability can be equated with predictability.

I don't think that predictability and innovation are mutually exclusive either. The "predictability test" can still be a good litmus for a genuinely new interaction - or at least for a good one. After all, aren't the greatest design innovations the perfect amalgamation of original compostion and familiar metaphor? Something can be both completely surprising and utterly "right" (= predictable) at the same time.

Yes... and this to some degree borrows from Peter Hong, an amazing UX guy now at Google.

Take findability + accessibility + predictability = usability,

But add in emotional appeal, because as we all know, having read Norman's Emotional Design, that products, services, things, that garner an emotional response, people consider more usabile, whether they are - or not.

And from Peter:
"The 'j' factor was inspired by Milton Glaser's life lesson # 5... which beautifully offers that "Less is not necessarily More", rather...

"Just enough is More"

'Just enough' of what matters to our lives so that the experience feels wonderfully satisfying. In life, there never is a set formula."

f(j) +a(j) +p(j) /l + e(1-c) = u

e = emotional appeal
f = findability
p = predictability
l = learnability
c = cost

That is my 2 cents :-)

- Will

On Sun, May 25, 2008 at 5:58 PM, Jeff Garbers jgarbers at xltsoftware.com wrote:

This is an intriguing discussion, but I fear "Usability = Predictability" is a bit of an oversimplification. So just to antagonize... Consider an application with 150 functions. The UI for this application consists of a single screen, with a short sentence describing each function in 6pt text. There is a 8x8 pixel green button next to each sentence. Instructions at the top of the screen say "Click the green button next to the function you wish to perform." Assume the text completely explains the function so any user can understand it, and when they click the tiny green [trim]

Anybody want to add some more terms to the equation?

Design is design?

-- Kontra
http://counternotions.com

Brilliant, insightful tautology, mate!

On Sun, May 25, 2008 at 6:11 PM, Kontra counternotions at gmail.com wrote:

Anybody want to add some more terms to the equation? Design is design? —

Predictable isn't the same as deterministic. A slot machine is/should be completely predictable: push the button, the "wheels" spin, and a payout occurs as appropriate. Which is why I don't like video slots with 9 or 15 payout lines. Even after seeing the payout results, I can't say why something won or not.

-- Jim Drew / CFM Designs
cfmdesigns at earthlink.net

Original message
From: Robert Hoekman Jr robert at rhjr.net

For the record, something about "usability = predictability" has bothered me since I first saw it written yesterday. I'm playing devil's advocate here to see if it holds up. I don't think it does. I'm relying on the IxDA community to come up with all those crafty arguments that make it fall apart.

I tossed this out to the Twitterverse last night as well. The most practical reply I got? Slot machines. Definitely usable while unpredictable.

Your equation, taken as a heuristic, is quite good and illustrates that usability (or user experience) is multi-dimensional. This heuristic equation will have different terms for different categories of product, but it makes the point that we should be more specific when we speak of "the usability of the product".

There is an equation called "Baker's Equation" that is somewhat similar, but focused on the liklihood of success of assistive technologies.

S = M/(P+C+L+T)
Where

S = Liklihood of success
M = disabled person's motivation to complete a task P = the physical effort required to complete a task C = the cognitive effort required to complete a task L = the linguistic effort required to complete a task T = The amount of time required to activate and control a device.

Chauncey

Take findability + accessibility + predictability = usability, But add in emotional appeal, because as we all know, having read Norman's Emotional Design, that products, services, things, that garner an emotional response, people consider more usabile, whether they are - or not. And from Peter: "The 'j' factor was inspired by Milton Glaser's life lesson # 5... which beautifully offers that "Less is not necessarily More", rather... "Just enough is More" 'Just enough' of what matters to our lives so that the experience feels wonderfully satisfying. In life, there never is a set formula." f(j)+a(j)+p(j)/l + e(1-c)= u e [trim]

The best answer? Women. (Crass, perhaps, but funny. Apologies.)

I counter that Men are predictable but not usable.

Posted from the new ixda.org
http://www.ixda.org/discuss?post=29451

Can I just say that some of the Usability 'equations' proffered to this thread bring tears to my eyes.

I look at this statement in terms of defining a causal relationship between usability & predictability. Or defining a set relationship. Essentially, Robert is saying that "everything which is usable is also predictable; and everything which is predictable is also usable." Some examples have already been provided that show the second part of the statement is incorrect - that some systems are alarmingly predictable in the way they suck.

So, we're left with "everything which is usable is also predictable". A longer version of this statement might be: "an inherent characteristic of a usable system is that it behaves in a predictable manner in response to user interaction." Implied in this statement is that little or no learning should be necessary, although Robert does not explicitly make that constraint clear. Some have argued already that a system which is predictable in the first instance could better be characterised as intuitive rather than usable.

Perhaps then we're looking to support the statement that: "*an inherent characteristic of a usable system is that, in response to user interaction, it behaves in a manner predictable by nominally experienced people*". Which now starts to introduce the notion of a continuum of predictability and usability which varies according to the experience of the user.

Since, as a discipline, we tend to believe in the notion that completely novice users should be able to approach a system interface and interact meaningfully with it, we - in theory at least - support the notion of usability in the absence of predictability. In other words, the predictability or lack thereof is a characteristic of the user, not the system.

We might then better characterise the relationship between usability and predictability as such: "an inherent characteristic of a usable system is that, in response to user interaction, it behaves in a manner that can be predicted with reasonable certainty by a person moderately experienced in the use of the same or similar systems".

To put this in more succinct terms: "usability = consistency". And note that the relationship is one-way.

Steve

2008/5/25 Robert Hoekman Jr robert at rhjr.net:

"Usability equals predictability." As in, if you can accurately predict what's going to happen next in an interaction, it's because the action you're taking is understandable, clear, logical, makes you feel confident, etc. If you can accurately predict what's next, the interaction has high usability. If you can't accurately predict what's next, the interaction has low usability. Shoot holes in that statement. http://www.ixda.org/help

Steve 'Doc' Baty B.Sc (Maths) , M.EC, MBA
Principal Consultant
Meld Consulting
M: +61 417 061 292
E: stevebaty at meld.com.au

UX Statistics: http://uxstats.blogspot.com

Member, UPA - www.upassoc.org
Member, IA Institute - www.iainstitute.org
Member, IxDA - www.ixda.org
Contributor - UXMatters - www.uxmatters.com

On 26/5/08 3:36 AM, "Robert Hoekman Jr" robert at rhjr.net wrote:

"predictability" = no changes from what is current expectations = no evolution of ui standards = we'd be stuck with the usability from the 1980's technology, not what we've got now. no? No. I simply mean that if you, say, click a link on a web page, predicting that it will land you on the About Us page, and it does indeed land you on that page, then that would be deemed to have a high level of usability. Likewise, if you click a command link or button‹regardless of whether it triggers an Ajax function or loads [trim]

I wouldn't classify that as "predictable", that's more "satisfying". You wanted something, you did something, you got the result you wanted. Satisfaction.

e.

Of course, there are rare cases of some things that are quite usable but aren't that predictable. I can think of some 'toys' that delight in their unpredictable nature:

The Wolfram Tones music generator ( http://tones.wolfram.com/generate/ ) can produce quite variable and unexpected musical passages, many which are hard to predict with any precision.

A flash toy, for creating snowflakes ( http://www.zefrank.com/snowflake / ) while only partly predictable, can produce some lovely animations, but one's control over the UI is something that would have to be developed over time.

Someone might argue that these are not 'usable' because they are merely toys. How churlish of you...

Of course, the UIs behind these toys is pretty good, because the instant feedback from them invites experimentation.

Justing injecting some whimsy into this serious discussion...

-David Drucker
david at drucker.ca

On 25-May-08, at 7:37 PM, Steve Baty wrote:

Can I just say that some of the Usability 'equations' proffered to this thread bring tears to my eyes. I look at this statement in terms of defining a causal relationship between usability & predictability. Or defining a set relationship. Essentially, Robert is saying that "everything which is usable is also predictable; and everything which is predictable is also usable." Some examples have already been provided that show the second part of the statement is incorrect - that some systems are alarmingly predictable in the way they suck. So, we're left with "everything [trim]

-- David Drucker
Vancouver, BC

david at drucker.ca

On May 24, 2008, at 8:54 PM, Robert Hoekman Jr wrote:

"Usability equals predictability." As in, if you can accurately predict what's going to happen next in an interaction, it's because the action you're taking is understandable, clear, logical, makes you feel confident, etc. If you can accurately predict what's next, the interaction has high usability. If you can't accurately predict what's next, the interaction has low usability.

We have a number of guiding principles we design by. One of them is "Predict before you click." And it's one of our most commonly referred to principles for the very reasons you highlight above.

Cheers!

Todd Zaki Warfel
President, Design Researcher
Messagefirst | Designing Information. Beautifully. Contact Info
Voice: (215) 825-7423
Email: todd at messagefirst.com
AIM: twarfel at mac.com
Blog: http://toddwarfel.com
Twitter: zakiwarfel
In theory, theory and practice are the same.
In practice, they are not.

On May 25, 2008, at 1:23 AM, Kontra wrote:

Not everything that's usable is predictable and not everything that's predictable is usable.

For example?

Cheers!

Todd Zaki Warfel
President, Design Researcher
Messagefirst | Designing Information. Beautifully. Contact Info
Voice: (215) 825-7423
Email: todd at messagefirst.com
AIM: twarfel at mac.com
Blog: http://toddwarfel.com
Twitter: zakiwarfel
In theory, theory and practice are the same.
In practice, they are not.

On May 25, 2008, at 10:27 AM, Eric Scheid wrote:

"predictability" = no changes from what is current expectations = no evolution of ui standards = we'd be stuck with the usability from the 1980's technology, not what we've got now. no?

No. Predictability means you before you perform an action, you can assert with a good degree of accuracy what will happen next. We've seen this with Tags. While most participants haven't got a clue what those things are, they think, or predict, that what will happen if they click on one is that they will see a list of items related to that word. They've never seen tags before, but they can predict with a high degree of accuracy what will happen next.

Cheers!

Todd Zaki Warfel
President, Design Researcher
Messagefirst | Designing Information. Beautifully. Contact Info
Voice: (215) 825-7423
Email: todd at messagefirst.com
AIM: twarfel at mac.com
Blog: http://toddwarfel.com
Twitter: zakiwarfel
In theory, theory and practice are the same.
In practice, they are not.

On May 25, 2008, at 1:42 PM, Martin wrote:

Things can be predictable without being usable. Any tech writer who has ever had the misfortune to have to write in Word will tell you that it screws up numbered lists. It does this in an annoyingly predictable way. Usable it is not.

Unfortunately true.

Cheers!

Todd Zaki Warfel
President, Design Researcher
Messagefirst | Designing Information. Beautifully. Contact Info
Voice: (215) 825-7423
Email: todd at messagefirst.com
AIM: twarfel at mac.com
Blog: http://toddwarfel.com
Twitter: zakiwarfel
In theory, theory and practice are the same.
In practice, they are not.

why is predicatability seen as a good or useful thing in todays competitive market? useable design can be both surprising and fresh, and people want to get on that learning curve just to try something new and play with a new product.
usability is a basic part of a good design, but its the creativity of the design that counts.

On Mon, May 26, 2008 at 9:04 AM, Todd Zaki Warfel lists at toddwarfel.com wrote:

On May 25, 2008, at 1:42 PM, Martin wrote: Things can be predictable without being usable. Any tech writer who has ever had the misfortune to have to write in Word will tell you that it screws up numbered lists. It does this in an annoyingly predictable way. Usable it is not. Unfortunately true. Cheers! Todd Zaki Warfel President, Design Researcher Messagefirst | Designing Information. Beautifully. Contact Info Voice: (215) 825-7423 Email: todd at messagefirst.com AIM: twarfel at mac.com Blog: http://toddwarfel.com Twitter: zakiwarfel In theory, [trim]

As a means of facilitating this discussion, the slogan "usability = predictability" has done a great job. Many assumptions, opinions and convictions have been made visible and we might even have succeeded in making some tacit knowledge explicit.
That being said, I'm always wary of slogans. By their nature, they swear themselves to be true, but no argument (not even this one) can hold sway at all times.

Slogans are a way of simplifying complex messages so that audiences can be swayed. They do not seek to explain or enlighten and therefore come apart during inspection.

Left unchecked, however, slogans get people into all sorts of situations where they act against their better judgement. Just take a look at the scrum-development list for a host of discussions where someone thinks they can't do X or Y because of principle 1 or 2, and someone with experience asks them to quit leaning on the rules and use their heads.

Judging from the length and intensity of this thread, however, we happily seem quite able to think for ourselves and counteract slogan-itis.

Now, who's up for a discussion of why "predictability does not, on its own, necessarily equal usability"?

On May 26, 2008, at 9:01 AM, Todd Zaki Warfel wrote: On May 25, 2008, at 1:23 AM, Kontra wrote: Not everything that's usable is predictable and not everything that's predictable is usable. For example?

Usable but not predictable: iPod Shuffle.
Predictable but not usable: IRS Form 1040.

Usable but not predictable: iPod Shuffle.

But that unpredictability is predictable : 

Martin

I was sitting in the front row of your closing keynote in Canberra Monday a week ago. You may remember me as "Donna's crazy boyfriend". And the comment? Basically, none of us look as good as we do in our promo shots - not negative, just the way it is : 

Ha! That's hilarious. But I think I'm insulted—that photo is only 2 years old. :  I couldn't have aged that much!

-r-

Now, who's up for a discussion of why "predictability does not, on its own, necessarily equal usability"?

Me!

-r-

On May 26, 2008, at 9:31 AM, james horgan wrote:

why is predicatability seen as a good or useful thing in todays competitive market? useable design can be both surprising and fresh, and people want to get on that learning curve just to try something new and play with a new product. usability is a basic part of a good design, but its the creativity of the design that counts.

Just because a design is predictable doesn't mean it's not new, innovative, or creative. The iPhone and Tags example I gave are good examples. Both are predictable, but innovative and refreshingly new.

Cheers!

Todd Zaki Warfel
President, Design Researcher
Messagefirst | Designing Information. Beautifully. Contact Info
Voice: (215) 825-7423
Email: todd at messagefirst.com
AIM: twarfel at mac.com
Blog: http://toddwarfel.com
Twitter: zakiwarfel
In theory, theory and practice are the same.
In practice, they are not.

On May 26, 2008, at 9:57 AM, Jeff Garbers wrote:

Usable but not predictable: iPod Shuffle. Predictable but not usable: IRS Form 1040.

Yes, laughingly, but admittedly true. Have you considered doing standup as a side job :  .

Cheers!

Todd Zaki Warfel
President, Design Researcher
Messagefirst | Designing Information. Beautifully. Contact Info
Voice: (215) 825-7423
Email: todd at messagefirst.com
AIM: twarfel at mac.com
Blog: http://toddwarfel.com
Twitter: zakiwarfel
In theory, theory and practice are the same.
In practice, they are not.