Ease of use – to the detriment of user experience?

User experience is, according to Wikipedia, "used to describe the overall experience and satisfaction a user has when using a product or system". I think this is a fairly decent definition, and will be the one I use for the purposes of this post.

Usability is, according a definition derived from Nigel Bevan,"the effectiveness, efficiency, and satisfaction with which specified users can achieve specified goals in a particular environment."

These two thing clearly overlap: a product or service with great usability is likely to translate into a good user experience. But what of sub-optimal outcomes – products or services that do not achieve perfect usability (that is, every product and service ever produced)? What are the trade-offs between usability/user experience, and ease-of-use?

The question can be more clearly phrased using an example. Imagine a complex software product, providing computational capabilities that no comparable software product can achieve. The managers of the company producing this product need to provide an update to keep ahead of their competitors. They have limited resources. Should they:

(a) apply all their resources to enhancing the algorithms to provide better results, or
(b) apply some of their resources to enhancing the algorithms and some to making the product quicker and easier to use

Easy, right? (b)? I guess that's what many people would say. Making a complicated, difficult, unwieldy product will increase support costs, put some people off buying the software, make the documentation more difficult and expensive to write, and so on. All of this is true. It's also true that if the developers think with more of a user-focus at the outset, then the product will be better to use without any additional resource.

But still, from a user experience point of view, (a) might be better than (b). It all depends on your user. If your users are all (or mostly) demanding better computational results over all others, then their user experience – their overall experience and satisfaction when using the product – is likely to be better with the more functional product than with a slightly less functional product that they can learn and use faster. Of course, if they can't get the results that the product is capable of, their user experience will be poor whatever.

The conclusion of this, I think, is that "satisfaction" is the key word in both the definitions. Something cannot be usable unless it satisfies the needs of its users, and neither can it provide a good user experience. And in order to provide satisfaction, we must "know our users". A product that's nasty to use will depress and upset most user experience professionals, but on a given day it may still be the best experience we can deliver.

User Experience definition
A paper by Nigel Bevan (discussing how usability can be approached from a quality perspective, but discussing how user satisfaction can be considered, measured, and tested)