Say you started a thread that asked a really good question. Not a question for debate, but a question that you want answered. When you get the answer that's right on the mark, and you're able to use it, you're never going to view the thread again, right? It would kind of defeat the point of leaving it open. I'd like to suggest to PC (or vBulletin, if that's a problem for them to handle) to let everybody close threads, but only (and only) those they started. So if Joe started a thread, and Bob started another thread, Joe could close his thread but not Bob's, and vice versa. That way mods would have more time to actually moderate and be able to spend less time closing threads because people couldn't close their own and they had to say "@mods: please close this now" (something I have done in the past many times). I think this would be a good idea.
Thank you for responses, should you decide to post one.
It's a cool idea, but there's not really much need for it. In the majority of sections you should use the Quick Questions thread to ask these things rather than making your own thread for them since it avoids cluttering up the section with one-post threads and just makes everything a lot more organised. Plus if there is a thread that needs closing then the section's moderator will usually do it at the first available opportunity and it only takes about two clicks, but if users are able to close their own threads then that'd also enable large discussions etc to be closed whenever the user wants so it could easily end up costing more time than it'd save. It's a nice idea, but I don't really see it being practical.
I don't think that'd be thaat good of an idea considering how many threads that aren't just asking questions. While this may be convenient for questions threads here in PCQ&F, out of all the threads on PC, only a small percentage of them are actually question threads. Most game-related sections have threads dedicated to quick questions regarding the games, so individual threads aren't necessary, and I don't think H-staff mind closing the few question threads we get in this section.
This could also be abused in threads where what happens to the thread isn't really up to the thread starter, so in the end I think it'd do more bad than good, and in any case, closing threads is part of what the moderators have to do, so if you want your threads closed, just contact whoever's moderator of the section about it.
I honestly don't think that would be a good idea. It interferes with the mod's job and I could see it causing miscommunication and complications everywhere, especially in over-active sections. And like Olli said it would definitely be abused by some people, there are reasons why there are mods to do this.
Not sure the "it's the mod's job" argument is very solid, but I'm more in the camp of thinking it could be abused. Not that long ago we had a person that was running a thread for a large group of people, had a long history and a lot of important stuff in the first post, and was trusted with it. He got angry over something silly and wiped the whole first post out. I'm sure someone locking a thread would often end up like that, someone locking a thread not because the thread is done but for a childish reason.