Threads and posts aren't always deleted on request. Unless it's for a very specific reason, such as sensitive personal information (names, phone numbers, addresses, emails), or if they're deemed to not make much a difference if they are deleted, we typically don't do it. Edits and closing of threads are more common.
If you want something to be looked at, you're more than welcome to PM one of us with whichever thread it is you're talking about.