Here are two related questions:
- When should moderators delete (not close) questions not posted by themselves?
- When should users with rep points ≥2000 vote to delete questions not posted by themselves?
I am asking these questions because the moderation tools (available to users with rep points ≥2000) showed that Suresh deleted the question 2246 on parent recently. I would understand it if it were closed, but I do not think that it should have been deleted.
My opinion is that questions should be deleted if they contain offensive/inappropriate/illegal material and so on, but questions should not be deleted just because they are poorly asked or off-topic. Closing is enough for poorly-asked or off-topic questions and, moreover, closed questions serve as bad examples. A secondary usage is that if many questions asked by one user are closed, that might tell something about that user to other users.