The Battle Between Usability and User-Experience

The main reasons why it is so hard to create usable products is that there is a conflict between a high-usability level and great user-experience. You might think this as strange, but there is a important difference between the two.

Usability

Usability is about the "ability to use" something. The aim for a usable product is to make it easy to use.

A product has a high level of usability when:

It requires less mental effort to use
the frequency of mistakes using it is less, or when the mistakes are less disastrous
it is more powerful, where "more powerful" means that it can be used to do more or do it faster
it is more learnable, that is, when a person can figure it out quicker

(source: Rensselaer Polytechnic Institute)

Making usable products is thus fairly simple. You have clear metrics you need to achieve, and you can analyze how to get a good result.

User-Experience

User-experience is not like usability - it is about feelings. The aim here is to create happiness. You want people to feel happy before, during and after they have used your product. To do that you need to take all kinds of things into consideration. Things like:

Environment
Colors moods
Smell
Touch
Audio feedback
Visual feedback
Trust
Branding
Show-off effect
Usefulness
Practicality
Coexistence
Emotional effect
Etc...

This is much much much harder to achieve. None of these things can be accurately analyzed. It is a touchy feeling kind of thing.

Why, for instance, does a Audi S6 give you a much better user-experience than a Ford Focus? I mean, in terms of usability they are pretty much the same.

The difference illustrated

Take roads. A Usable road is one that is wide and straight (less mental effort), with no oncoming traffic (less mistakes, less mental effort). One that enables you to get from A too B as fast as possible (more powerful) and one that has a consistent and clear use of signs (high learnability).

In short the most usable road is a freeway. But, a freeway is also directly boring in terms of user-experience.

A road with a high level of user-experience is completely different. It is a twisting mountain road (visual). Now you got great scenery (visual, emotional), the smell of nature (smell), the excitement from the climb (and the sheer cliff only feet away). You got little friendly signs put out by the local, who sells fruits along your way (show-off effect). Every city is slightly different (branding, emotional, environment). You feel happy when you see the locals wave when you pass by, and you stop let a sheep pass (emotional, trust, coexistence).

But a mountain road is far from a usable road. It is much harder to drive on, it is difficult to learn, you can't go as fast and the risk of making a mistake (taking a wrong turn or cashing into a sheep) is much greater. But, a mountain road will give you a much better user-experience than any freeway could ever do.

Creating synergy

The reason why we have so few great products is because of this difference. Most developers try to find the right balance between high usability and high user-experience. A bit like trying to turn a mountain road into a freeway. It simply does not work. You end up with mediocrity.

Instead you need to create a synergy. A Synergy is when 2 + 2 = 37.

This is not easy. It requires a bit of luck, a great deal of intuition (female intuition is helpful), a great sense of humble pride, and something called "usable happiness (*)".

Flickr, The Sims, Apple iPod, Ta-Da list, MySpace, Google Picasa, Virtual Earth, Audi S6, Mac Mini, any Pixar movie, and iRobot Roomba are all great examples.

* Usable happiness: is a product that is simple to use, and makes you smile every time you use it.

Make it easy to be happy

It is far from easy to create a great product on demand, but it is possible.

First of all, do not focus on usability or user-experience. Do not directly try to achieve to create synergies. Do not try to create a great product. None of these things will get you any closer.

Focus on making it easy to be happy, and usability, user-experience and greatness will come all by itself.

Instead of making a product management web application, make it easy to finish great projects. Instead of making usable instant messaging, make it easy to have interesting conversations. Instead of making a powerful web writer, make it easy to write exciting stories.

The result is that you use usability to take away all the things that distracts you from happiness, and you use the elements of user-experience to empower what people can do.

... and now you got a great product.

The International Standards Organisation's definition of usability already includes both the functional and feeling components: "The extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of use." (ISO 9241-11 (1998)).

Thomas Baekdal

Writer, Project Manager and Interaction Designer

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Thanks for the heads up Alexander. I did not know about that one.

There are many definitions on both usability and user-experience (just read Justaddwater.dk's post about it - link above). I cannot say one is more accurate than another.

BTW: Does anyone have a link for a ISO 9241-11 document (free web version or PDF).

Narciso Jaramillo

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Hi,

I agree with you that there's a distinction between usability and user experience, but I think it's actually a mistake to describe them as being opposed to each other-they're different, but not conflicting, and not entirely uncorrelated. I've written a blog entry with some thoughts on the subject.

Thanks,

Thomas Baekdal

Writer, Project Manager and Interaction Designer

follow me on Facebook, Twitter, Flickr, or visit my website

Thanks NJ for an excellent blog entry. I have posted a comment on your site.

Everyone else. I recommend that you take a few minutes out of your busy lifes to read NJ's entry. It explains the very important concepts of challenges vs. frustration. Something that is relevant to this article.

Nikhil

NJ, you are great. Your writings on User experience are superb!. Thanks a lot for all these articles.

Ash Donaldson

Thanks for the great road metaphor!

In describing the difference between usability and UX in my presentations, I often cite the case of Ernest Dichter - a business anthropologist and motivational researcher in the 60's - one of the earlier 'user experience' professionals in my books.

He was commissioned by General Mills to see why their highly usable, just-add-water pancake mixes were a hit, but their just-add-water cake mixes were a flop. So, he went out and did his research - and came back with his answer. He said:

The cake itself was a symbolic gift that a woman gave to her family or sweetheart, and a just-add-water cake mix cheapened that love.

Dichter suggested that the mix require a fresh egg and some oil, and so, Betty Crocker cake mixes were born. The addition of these ingredients *decreased the usability* of the cake mix, but *increased the user experience* - propelling Betty Crocker to the number one cake mix in the world.

On the other side of the coin, while studying the layouts of ATMs, Japanese researchers found that - even though were all identical in functionality, number of buttons, and how they operated - the ATMs that had their buttons and screens arranged in an attractive fashion were consistently rated by users as working better. So increasing user experience, increases perceived usability.

As for the standards: As one of the people who works on the HCI/Human Factors standards for ISO, I can safely assure you, since it's an International Standard, it's not available for free anywhere. :(

That said, the guys at Userfocus created a wonderful "Bluffer's Guide" to 9241 for only a few dollars here:

http://www.userfocus.co.uk/resources/iso9241/index.html

If you want to know about the broader range of ISO standards relating to HCI/usability and software human factors / ergonomics, take a peak at Nigel Bevan's papers:

http://www.nigelbevan.com/cart.htm

(unfortunately, the link to his latest "International Standards for HCI" paper is dead, so you might have to drop him a line to get a hold of it)

David Travis

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I enjoyed your post, but if you took the ISO definition of usability rather than that of the Rensselaer Polytechnic Institute, you'd see that it includes user satisfaction, alongside user effectiveness and user efficiency. So to follow your "road" metaphor, the freeway would be more effective and efficient but it would lose out to the mountain pass in terms of user satisfaction.

This is what makes the ISO definition so powerful: you have to consider all three measures to get the whole usability picture. Interestingly, the ISO definition of usability was formulated long before the term "user experience" became common currency, yet it serves as a perfect definition of UX without modification.

amol

Thanks! I appreciate it

Shiv

The road example is, unfortunately, misleading and confusing. Both roads, in reality, need to be usable and have a positive user experience. One road was just built to go up a mountain, the other to get from point A to B. Those differences are not usability, I'm afraid. If anything, the metaphor is that they are two pieces of working software, one meant to do something different than the other. Both will feature very similar usability requirements, as I will illustrate:

The "usability" in this example is that both roads are free of construction and potholes, have guardrails and signs pointing the correct way, have speed bumps and warnings when there are curves and exit signs if it's that kind of road.

The "user experience" is that the road signs are bright and appealing and easy to read, that they're of an attractive color, that they have icons to further explain and enhance the sign.

Usability and user experience are NOT to be pitted against each other. They are not in competition. They MUST be used together, and that's what creates a synergy, not a weakness.

It's common knowledge among UX developers that user experience just "enhances perceived usability." With some modification, your road metaphor could work. But as it stands now, it's not doing any service to the community.