Since this thread started, I've been trying to find the post in question but haven't found it in order to PM an answer. But you just gave me a clue as to what MIGHT have happened, myekem. One common scenario is where someone starts a thread by asking a question say in the Breaking Down... section. Then someone suggests making an introduction followed by more responses. I come on in the morning and see a thread by some with a low post count and check. There's no introduction thread. I delete the thread and send the new member a PM asking please make an introduction in the Off-topic section - There went your post. Another scenario is where a new member posts on an old thread (often starting a whole new subject). Then there is a post telling the person they should make an introduction. I'll come along and delete the new person's post and the replies. This is for continuity of the thread. Imagine if I left your post telling someone from a year ago to make an introduction.
Does either of these seem like what happened?