On math.SE (and SE 2.0) there is a feature that -4 (or lower) questions do not appear on the front page, unless an edit to the question was made (not even to the answers!). If such feature exists on MO then it's not a bad idea to just downvote the question until it has -4.
]]>At the current pace, most questions that are completely unsuitable for the site take about 4 days to go from first asked, to deleted. Typically such questions are closed quickly. The extra 3+ days allows the user some time to revise the question so that it could potentially be re-opened. If that doesn't happen, then the question is considered for deletion.
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