I figure this is a long shot, but I recently came across this post. It was deleted by several users over a month after it had been posted, answered, and closed as a duplicate.
Does anyone know why this question might have been deleted? My impression is that the general policy is to not delete questions except under some specific circumstances, and this meets none of them.
Clarification from the comments: I'm under the impression that we delete ongoing contest questions, spam and simultaneous cross posts, questions where discussion has devolved to the point of intervention becoming necessary, presumably questions containing illegal content. I wasn't aware that we regularly deleted closed questions, as implied by Jonas Meyer's answer. I have especially observed a tendency to be more lenient in including well received questions or answers and this has two 5+ answers.
Since this seems to be a point that is confusing people, I'm not asking that the question be undeleted. I'm asking about why we delete questions like this.