For some reason when I’m developing something new I always end up changing my design twice. Note, I’m not talking about architecture here. Architecture is a higher level concept and as such isn’t killed by implementation detail the way a design is. I think there is a reason for this multi-version development though.
The first design is basically a prototype exploring possibilities. At this point I’m not sure what the best solution is or even what techniques might be best to use. It only just does the job and is probably not very elegant or efficient. Not something to be proud of.
The second is usually a great design but, more often than not, flawed with a super hero style weakness. It will be elegant, efficient and cover every requirement imagined. The only problem – it will never be finished. This second iteration is usually complex, over designed and would take an eternity to implement.
After a good dose of reality, the third version takes shape. It’s much more practical, easier to maintain and solves only the requirements that are actually needed. These three designs are usually quite different. Not what the XP crowd would call iterative implementations but the end result is similar.
I think it’s important not to get too attached to any one way of doing things. I see some who start coding and stick with their first design to the bitter end no matter what. People often complain that a v1 product is OK for early adopters but not general consumption. Iterative design like this enables that sought after v3 product in your first release. Just don’t take three times as long to implement it…