When I first heard it suggested, it seemed almost obvious that moderators should say something about the PSQ (problem statement question) issue. However, after some reflection, I no longer consider it obvious.
I will post as answers the three positions I have on the title question.
(I hope PSQ is an acceptable abbreviation to all)
Since it wasn't clear, a problem statement question is a question that essentially (and often, literally) consists of nothing more than the statement of a problem.
Here is a recent example. (with the added bonus feature of being three problems in one question)
(edit by J.M. and A.K.)
Since it would seem that there are people in meta who can't be arsed to read gentle reminders in comments: $\Large\textbf{don't bloody downvote the answers!}$ It's a poll; $\Large\textbf{upvote only the answer(s) you agree with}$, and if you agree with none of them, express your displeasure in a comment, or write an answer that more suits you.
Sheesh...