It’s great that unit testing is getting a lot of attention. There are xUnit frameworks for every language, and secondary tools are emerging. It is also becoming common to designate some developers as “in test”, meaning that they develop software to test their organization’s development projects. More importantly though, developers are thinking about testing, educating themselves, and taking responsibility. A similar movement needs to take place in software usability.

A usability department is more rare than a QA department ever was. Most developers will never work with a usability expert, and even if they did, they still would have a lot of usability decisions to make. Like other aspects of software creation, developers need to learn the concepts of usability. But, unlike many aspects of development, usability is not clearly quantifiable or automatable. There are some rigorous methods, but usability knowledge is essentially a set of heuristics and the ability to imagine yourself as the user.

The heuristics can be learned either by example or counter-example.  But imagining yourself as the user is a little harder.

You spend all day with the software you create. It is probably one of the most important things in your life—it pays for your food and rent. You know everything about it.

Your users prefer not to even think about your software. They have tasks they are trying to accomplish (to earn money to buy food and pay the rent). Even vitally important software, like my web browser, my e-mail client or my compiler, are insignificant when compared to my family, my job, paying my bills, and having fun—and I would replace them in a second if they got in the way of those things. Keep that in mind.

The only way to learn about your users is to watch them use your software in their environment, with their distractions. You must learn what they typically know, the words they use, the things they care about. If you are a developer, don’t let yourself be shielded from the users. You need to meet them and hear what they have to say. You need to ask questions. And by “users”, I mean the people who use your software—not their bosses or their IT staff or your boss or a UI expert or a marketing guy or whoever. If you manage developers, put them in front of users.

I have learned more about financial trading software by sitting with traders than the entire time I spent writing it. There are idiosyncrasies that I would never know unless I watched them work (how little time they have to do a trade, how many hands they have free, the distractions, their patience level, their technical level, their vocabulary, etc), and I guarantee that your users are similarly unique.

For further reading: Bruce Tognazzi’s First Principles of Interaction Design, Joel Spolsky’s UI Design for Programmers series, Jakob Nielsen’s Ten Usability Heuristics. Learn from the mistakes of others by looking at the original User Interface Hall of Shame  or this other one from Pixelcentric.