Dhanji Prasanna wrote a great article about his experiences on the Google Wave team, and the difficulties of working in large development teams. He brings a particularly interesting perspective to UI engineering:

To say we should have been better prepared or organized is to miss the point – large teams starting on a new project are inherently dysfunctional. One common consequence of all this chaos is that experienced engineers seclude themselves to their area of expertise. At a company like Google, this generally means infrastructure or backend architecture. A major externality of this is that fresh grads, and junior engineers are shunted to the UI layer. I have seen this happen time and again in a number of organizations, and it is a critical, unrecognized problem.

UI is hard.

You need the same mix of experienced talent working in the UI as you do with traditional “serious” stuff. This is where Apple is simply ahead of everyone else – taking design seriously is not about having a dictator fuss over seams and pixels. It’s about giving it the same consideration that you give any other critical part of the system.

I’ve experienced this first-hand, and I’ve also seen what happens when backend developers are forced to do UI work (which can happen for a variety of reasons). I’ve heard developers say that they don’t like to do UI work because “it’s not real programming”. They prefer to focus on the real stuff, not this fluffy CSS/JavaScript thing.

Whether or not their perception is accurate is only one part of the discussion. What I want to point out is this: If you make backend developers do front-end work that they’re not passionate about (or worse, work they find embarrassing to do), they’re not going to be motivated to expand their knowledge and do a good job. That’s unfair to everyone and disastrous for the product.

It’s essential to have dedicated UI engineers in an organization so that everyone can focus on the technologies that they’re obsessed with.