It has given me a great understanding of how important perfection is. At school everyone said, "you spend too much time perfecting everything" or "spread your* effort, rather than spending lots of time on one thing and rushing another." But now, in programming, knowing where to put the time and effort is the most useful skill I could ever need.
Also, I can barely use the mouse correctly anymore, except when playing video games.

*Here, my Google Keyboard suggested: legs, wings, Marmite. 😕