Just as the summit marks the halfway point in your climb of Everest, working code marks the halfway point to "done." Call it done when you transform your working code into elegant sustainable tools which you and your team can leverage.

This book changed my approach to coding be it simple scripts, applications or build systems (I'm a release engineer, best job ever). The book couples excellent advice with real world examples that drive the point home. There's a section where the author takes readers step by step through a refactoring which cemented many techniques for me.

A very worthy read.