Most forums don't allow threads to be deleted unless there are exceptional circumstances. Threads don't belong to the poster, but to the forum. Deleting them is an insult to the people who've replied, and take away a resource from other members who might have gained advice or knowledge from the thread. But the mods are friendly and helpful. You can always ask, and they won't refuse without a reason.
That's how it is - its in the rules you read and agreed to when you joined... point is that the thread starter doesn't own the thread so if a lot of people have put time into replying to it, why waste their time by deleting it
Not in my opinion. Once people have added posts to your thread, why should YOU be able to delete what THEY have written?