You can closevote your own questions if they're not up to the site's quality expectations. You automatically unlock this privilege at 250 reputation, and it has been around for a while now. As said in the Privileges page:
When should I close my own question?
Questions that are sufficiently off-topic, as outlined in the FAQ, should be closed by casting close votes. Common reasons for question closure are:
- You asked a question that was asked before
- You asked a question that is off-topic
Typically, though, most self-closed questions are either duplicates of another post (that you didn't just see), or they can't be reproduced because they were fixed.
Remember, closing as a duplicate isn't a punishment -- it acts as a signpost to guide new users to other questions that are far more likely to help them solve their problem. Similarly, closing your own question as off-topic when needed allows us to focus our efforts on solving other problems on-site, wherever they exist.
This is not a new feature but a new privilege for you since you have earned 250 reputation.
You can close vote your own questions (on any site), but the vote is no more powerful than usual. This is nice, since it gives the community a chance to help to make a decision about whether the question really deserves to be closed, or might actually be possible to answer in a way that helps others. Questions and their answers are not just here to help the OP after all :)
That said, when I decided to vote to close one of my own questions, I did so, and I was in chat at the time and dropped in a link to it, saying "VTC my question as no repro since the problem got fixed in an update to the application" and a mod kindly saved everyone the trouble...
