If you know me, you know that I usually don't completely agree with Jakob Nielsen. However, in this post about Agile and UX, I really can't disagree with anything he says in the post. I haven't read the entire report (I don't have an extra $148 at the moment) so it is possible that I will eventually find something that I can disagree with.
One of the things that really stands out for me is this quote:
You can't just design individual features; they have to fit together into a coherent whole — a whole that must be designed as well. Bottom-up user interface design equals a confused total user experience (the Linux syndrome)I am not really a Linux user so I can't speak to the User Experience of Linux in general, but the idea that "Bottom-up" design leads to poor results is just plain obvious. Not to mention in my experience I have seen it happen numerous times. In contrast I have see first hand how a small investment "up front" in design proves to really pay off.