I've occasionally noticed an OP who will edit their own question and destroy it completely, always leaving some kind of graffiti-like scrawl in its place.
This seems to happen on low-quality questions by low-rep users, and the moment of self destruction tends to occur after the question is closed or otherwise devolves into a communication breakdown between the poster and the community.
Here are some examples:
It seems like the poster usually does this in anger (1st and 3rd example), or else is just confused about how to delete their question (2nd example).
My question is about how this should be handled. In the past I wasn't sure, so I always flagged for mod attention. However I notice the solution on all of these was to just do a rollback (I did this myself on the 2nd example after nothing happened). Is this a good enough approach, or should a flag be used? What about with particularly obnoxious users like in the third example, where the guy came back to do it again?