I made a comment in a post several minutes ago.
Very soon, before I had the time to edit, it got deleted and I also noticed that I lost about 40~50 reputation, without any notification. Nothing is shown in the reputation history.
The comment is the only thing that I have done in at least 12 hours, so I think the two events are related.
I have seen that moderators can delete comments, and flagged comments can get deleted, e.g. in this question. But I didn't expect that kind of reputation loss without notification.
Is it a normal situation that one can lose reputation without receiving any notification? And what is the logical basis of that, if there is such a rule?