When a user wants to delete their account, if they have posted 0 or 1 times, their account is deleted immediately; otherwise, they have to wait 24 hours for their account to be deleted after requesting deletion.
Recently, we've been encountering a troll (visible to members of the Charcoal SO Team, 404 error for others) who deletes their account promptly after posting their trollish answer in order to evade the automated anti-recidivism systems. They seem to know that if a moderator deletes their account, an automatic suspension will be recorded under the account, which will be "reinstated" by the system through their IP address if they recreate their account; deleting one's own account immediately after trolling is one way to bypass that, as it's not possible for a moderator to suspend a deleted account.
I believe that one of the reasons why we allow users to immediately self-delete their account after making one post is so that if users decide they don't want to use the site after just testing the waters, they'll have a faster time leaving. I believe it's mostly there for historical reasons, since back when it was implemented, users who didn't meet the criteria for immediate self-deletion had to contact SE to have their accounts deleted. I don't believe it has much utility anymore, since users can now start the 24-hour timer by themselves, immediately.
Should we restrict immediate self-deletion to those who've made only 0 posts (and not 0 or 1 posts)? (I would have suggested allowing immediate self-deletion for those whose one post is received positively, but this isn't a good idea given the specific nature of this particular troll, whose posts may be upvoted by users who don't know about them.)
Just to make it clear, this is not an actual request to do this. Rather, I want to gather opinions before filing an actual feature request.