Jeff Atwood is one of those rare developers who has a real passion for UI design and User Experience. In his most recent post regarding Stack Overflow he says some interesting things about usability. The post has an incendiary title (“Code: it’s trivial”) but that’s not the interesting bit. Here a quote:

“Developers think cloning a site like StackOverflow is easy for the same reason that open-source software remains such a horrible pain in the ass to use. […] If you then tell a developer to replicate StackOverflow, what goes into his head are […] two SQL tables and enough HTML to display them without formatting, and that really is completely doable in a weekend. The smarter ones will realize that they need to implement login and logout, and comments, and that the votes need to be tied to a user, but that’s still totally doable in a weekend; it’s just a couple more tables in a SQL back-end, and the HTML to show their contents. Use a framework like Django, and you even get basic users and comments for free.

But that’s not what StackOverflow is about. Regardless of what your feelings may be on StackOverflow in general, most visitors seem to agree that the user experience is smooth, from start to finish. They feel that they’re interacting with a polished product. Even if I didn’t know better, I would guess that very little of what actually makes StackOverflow a continuing success has to do with the database schema–and having had a chance to read through StackOverflow’s source code, I know how little really does. There is a tremendous amount of spit and polish that goes into making a major website highly usable. A developer, asked how hard something will be to clone, simply does not think about the polish, because the polish is incidental to the implementation. […] every day, our tiny tiny little three person team […] starts out with the same goal. Not to write the best Stack Overflow code possible, but to create the best Stack Overflow experience possible. That’s our mission: make Stack Overflow better, in some small way, than it was the day before.” (Emphasis added)

Jeff describes Stack Overflow as “sort of like an anti-experts-exchange” (who are well known for their dodgy design and SEO practices, and up until recently have been dominating organic search results). A quick look at Alexa shows that Stack Overflow has a lower bounce rate, more page views per user and a longer average time on site than experts-exchange. If you’ve used them both this wont come as a surprise to you, but it just goes to show that once again, good usability and generally good business practices translate into measurable performance indicators.