Per (as far as I can tell) the original: http://c2.com/cgi/wiki?MakeItWorkMakeItRightMakeItFast
1. Make it work.
2. Make it right.
3. Make it fast.
1. Make it work.
2. Make it right.
3. Make it fast.
Note: The debates over LISP, OOP, Cleanroom, Smalltalk, and so on are all especially interesting.