Once in a blue moon, I've wanted the ability to downvote my own answer to some question. (Here's one (admittedly silly) example.)
Obviously upvoting one's own posts is out of the question. But down is different. Voting my own answer down can help me improve the site by pushing my answer lower in the ranking than another answer with a better or more situation-appropriate alternative. It's not something I'd do often, but I would use this feature if it were available.
If implemented, I'd expect this feature to operate just like downvotes on other user's posts. That is:
- I get a few seconds to undo the downvote;
- I get to remove the downvote after an edit to the post;
- I lose a point for placing the downvote (CW excepted);
- I lose two points for receiving the downvote (CW excepted).
If you're noticing that I'd lose 3 points for downvoting my own non-CW post, congratulations! You can add!
I can think of a couple of potential downsides to this change. The first one may be a dealbreaker; the second is probably not that big a deal.
- Strategic downvoting of oneself: since you can undo the vote after an edit, and you can always edit your own posts, someone could downvote themselves soon after posting (especially on a FGITW answer) to garner extra sympathy upvotes.
- Badge collecting: the Peer Pressure badge just got easier, because if you have a -2 score on an answer, just downvote and delete for an instant badge.