Cleaning up code is like cleaning your room. It's a bit of work. But you'll feel happy and relaxed knowing everything is all tided up and certain things are exactly where they should be.
Imagine working as hard as you can to ace all of your classes, only for some IDIOTS to ruin any chance you have of getting things done. I have 2 assignments due for Friday and I don't think I'll be able to finish one of them. That gang can go shove it.