<p><strong>I routinely review every active question.</strong> </p>

<p>Old questions become active whenever they're touched by somebody.  The "Community" bot often touches old questions that might have some value (because they were upvoted or answered).</p>

<p>I can no longer do this as thoroughly as I used to because there are about 200 new active questions every day.  That's why we have multiple moderators!</p>

<p>(There is one class of exceptions: some community members are in the habit of making tiny modifications to large numbers of questions all at once.  I recognize those people and the sequences of threads they have touched, and usually just skip over such posts.)</p>
