When you answer a question, there's a little box in the bottom corner of the markdown box where you can select for it to be a 'Community Wiki' answer. This makes the post more readily editable by lowering rep boundaries and so on, to give the community a larger say in what the answer says.
So why can't we do this with questions too? Just like with answers, there are definitely times when this option would be beneficial.
Questions obviously can be wikied as evident in this post and this post, but having looked through the privileges, this doesn't seem to be something that can be earned through rep. I understand a non-moderator user being unable to wiki another users post no matter their rep, but I don't understand the inability to check that box on your own posts.
Why is this feature left to moderators alone?