Suppose someone only asked 30 bad (closed or downvoted) questions in 30 days. This person probably would be "shut down," either by a timed suspension, or by the algorithm that says, "this site is no longer accepting questions from this account" before the 30th question.
But suppose those 30 bad questions are spread over three years, that is at a rate of one question every 36.5 days on average. (This interval is longer than say, a 30-day timed suspension.) The asker is curious, not too bright, (probably) not harmful and visits the site "from time to time."
Is this a different situation from the first (30 questions in 30 days)? Assume that no flags are involved. Although the algorithm is secret, would it focus more on "one bad post within the past 30 days" or "30 bad posts cumulative from 2010," or something in between?