perfect design is an oxymoron
Les Orchard and Chris Winters have recently blogged a few comments about design. Both have commented that there is no perfect design. But they haven't stated that strongly enough.
I've done a lot of design. Lots of my undergrad work was in design methods and computer applications in architecture. I've done architecturall design, graphic design, network design, interface design, software design, and systems design.
Design inherently involves compromises and trade-offs between drastically opposing concerns. Elegant design is tasty and satisfying precisely because it is impossible to find a perfect balance in a collection of opposing concerns.
Les Orchard: There is no perfect software design
Chris Winters: Perfection and organic growth