So there has been a lot of discussion about what purpose a code review will have in this site. Whether or not users should be able to bring a "Help me my code is broken" to this site.
So, what does a code review mean to you? what are the pre-conditions for a code review (input) and what kind of outcomes (output) can a user expect?
Add your thoughts below, 1 idea/theme per answer please.
(this should be a community wiki, I know, but no option at the moment)