> I think that's the key. Unlike software development, where you can improve things here and there incrementally, with design you need to have an overall view of what you want to do, where you want to get, how the final product should look.

I think many software developers would say exactly the opposite (and I think both would be wrong.)

Except the marketing effect of a new UI, do you have literature (or just easy explanations) that would help me understand why this should be the case?