Given the current economy and the housing market here in Florida, we have been talking a lot about renting versus owning a home. How does this have anything to do with code? Glad you asked. In the life of any given application, you are probably in it for only a short time (relatively). You might be on the team that builds the version 1.0 product or you might be on the team that is supporting version 6 of a product on version 8. Whatever the case may be, more often than not, you are just there renting the code.
I think this is an important fact to remember. My friend Brain Button taught me a long time that I am not my code and that I definitely do not own it. When I put myself in the mindset of a renter instead of an owner, the idea of The Broken Theory makes perfect sense. When you rent a home / apartment / car, you sign an agreement to take the best care of the thing you are renting the best that you can. Why should that not be any different for code? No matter how you decide to take care of the code you are renting, you should always feel good when you turn (check) it in.