It can be kind of a relief to freely acknowledge the reasons your thing might suck, one way or another. Ideas can somehow be less scary written down than when just hanging around as possibilities in your head. If you think your bad self-review is the only reasonable way to look at things, then maybe you have a real problem, but hopefully your reaction is to put it in perspective somehow--to consider the good things balancing the bad, or why the objections aren't valid or aren't fatal, or at least that the world keeps spinning and you are not your work. And then when life or other people's reactions come around, your reaction is a bit less surprised and maybe more grounded.