Actually that is what separates the professional from the hobbyist (I've seen both bad professional programmers aka 9-5ers and amazing hobbyists), and when I work professionally both in my startup and in a previous life as an employee I put on my waders and jump right into the thick smelly bog. But especially when you take a couple of years of vacation and work for fun on projects that interest you, you find out that sense of ickiness is probably the best indicator of code rot.