A few minutes ago, I asked a stupid question on Meta - or rather made a mistaken bug report. A few seconds later, I realised it was stupid and deleted it.
So far so good - but I couldn't help noticing that 2 people had already read it, and I wanted to appologise. But editing the question or adding a comment would mean wasting even more peoples time, leaving a stupid question visible when it could have been deleted already.
So, I thought, perhaps it would make sense to have an optional deletion comment. Delete the item immediately, but request a comment, and (if given) push that out to anyone reading the item, similar to the "new answers" thing that's displayed when you're writing an answer.
That way, I could have said "I'm an idiot, sorry for wasting your time" when I deleted my stupid question, and perhaps have wasted a bit less of at least two peoples time.
Of course I could have avoided wasting peoples time entirely by not being stupid - but that's a bit challenging at times.