I haven't digged much, but it's my understanding that the dev suffers from perfectionism and that nagging feeling that is still not good enough, could be better. I guess I get the feeling, but things can always be better no matter how great they are, so you have to decide to just stop instead of trying to improve it forever. You can always try to start from scratch and make something new that is even better.
At least credit where credit is due, he's competent, determined and a hard worker, for all my gripes, he's still a top-notch, model developer.