In this question competetive viable or junk? I left a comment explaining why the question was a bad match for this SE, and I want to think it was constructive criticism, nothing remotely delete-worthy IMHO. It got deleted along with a string of less helpful comments. I would like to know why my comment got deleted.
This is not the first time a comment of mine was deleted that was IMO perfectly fine. Comment deletion should be a lot more transparent so people can learn what got it deleted, or to appeal the decision.