To pile on with the comments about avoiding perfectionism and having business sense, I've seen projects and teams go under because they tried to apply every technique they'd heard of that could improve quality control without taking the project budget into consideration.

Cutting corners too much is equally as bad as being a perfectionist as well. Perfectionism might even be worse because you'll probably never finish anything.

Software can always be made better. The important development skill is knowing what's good enough so you're not burning time for little benefit.