Most of the forums I've ever been a part of allowed their members to delete their posts, or lock their topics if needed. Some did it differently, and within reason, of course—some would only allow you to delete a post within a set amount of time, or you had to wait 24 hours before deleting whatever you wanted to delete, and so on. I do remember two that actually had a topic specifically for members to request post/thread deletion, so maybe that could be a thing here given we have other threads that follow that motif. Deleted posts would also reflect in their post count.
Double posts, accidental posts in wrong threads, creating a topic when you meant to reply, realizing your response was stupid after you posted it, I have no clue.
You might not have a clue, but those are some good reasons for someone wanting to delete a post or two.
My advice to
telly would be to just edit your post if you feel it doesn't reflect what you wanted to say properly, or just put a, "Sorry, din't mean to post.", and leave it at that.