Chapter 1 of Joel Spolsky’s User Interface Design for Programmers is titled “Controlling Your Environment Makes You Happy” and contains a story of Joel’s time working in a bakery which concludes:

The more you feel that you can control your environment, and that the things you do are actually working, the happier you are.

This is why I Use My First Commit to Fix CRAP. It takes 5-10 minutes and lets me exert some control on my environment. I start each day with a small success. If I feel frustrated later in the day, I just do it again.