Criticism at the wrong time, even if it's legitimate criticism, can be seriously damaging and make the writer lose faith in what he's doing. It's the timing that's all-important.
Donna TarttI'd always rather stand or fall on my own mistakes. There's nothing worse than looking back, in a published book, at a line edit or a copy edit that you felt queasy about and didn't want to take, but took anyway.
Donna Tartt