The folks over at 37signals, whom I respect greatly but often disagree with, have some very specific ideas about how you should design and develop web applications, especially in that order. They’re big supporters of the idea that the UI is the app, and I think that’s a really valid idea. They’ve talked a lot about how the interface is too often something that is “painted on” at the end and it hurts the final product, mockups should be html and css, not photoshop or (in my case) MS Paint, etc. They like design that they think is good (different from good design, as they often admit themselves).

One problem I have with this whole “design first, make it work later” idea is that it really lengthens the feedback cycle. The idea that a mockup made of things that can be clicked makes sense, but not when it comes at the expense of getting feedback on what you’re doing, which is useless until those clicks are functional.

If you give almost anyone a choice between testing ugly functionality or attractive emptiness, they’ll choose the former. That testing and feedback is crucial, even if you ignore most of it (which is another 37s dogma that isn’t really relevant).

They make the analogy to “paining on a UI” at the end and the “plumbing” behind it. It’s odd, because I doubt a lot of houses paint the walls before the plumbing is installed.