Writing Software People Want to Use
Perhaps the most succinct -- and best -- advice about software development that I've ever come across. Jamie Zawinski, in this post about groupware, boils it down to: If you want to do something that's going to change the world, build software that people want to use instead of software that managers want to buy. So simple, and yet nearly impossible to accomplish.
It's worth adding to "and instead of software that purists want to praise".
Crappy software that does what users want will do better than well-architected, clean, standards compliant software that doesn't quite do what users want.