That's different, of course, from making your best effort and then asking someone who you think is good at programming to find all the places you could do better.
The benefit is, the reviewer gets to learn a different part of the system, and the person getting reviewed gets his code scrutinized. It is a very beneficial system.
As far as showing bad code: There is a different between delivering crap and delivering code you are satisfied with. If you are satisfied with it, thats when scrutiny is necessary. You need to get a feel for when the code is good enough, because you can spend all your life making it just a bit better. Same kind of stuff applies to artists, you just need to know when to stop improving and start letting others scrutinize the work.