Here is an annoying issue.
I am signed up for emails when someone posts a mugshot on Nicks thread. So I get emails that say that someone new has posted. Sometimes when I go and look, nothing is new. Later they post a photo with a note that they needed to downsize the photo a few times. This means they tried to post and it was rejected.
The problem is that even though the post was not accepted by the server, something triggered all those emails to be sent out saying that something is new. Thereby taking up bandwidth for no reason. Plus it is very confusing to see a message that says something is new and then there is nothing there.