log(affected_users / time) * stupidity_of(bug). If nobody can use the core functionality of the app because of something that would have failed a
perl -ccheck, that yields a lot more angst than "some non-critical task doesn't work for one (uniquely configured) client when the day of the month is 29 or more," even though the latter is often more difficult to diagnose.
Yeah. I crashed our site the other day over a trivial logging change, intended to gather debugging information for a rare condition of the latter sort. It was so trivial it couldn't possibly go wrong, meaning
stupidity_of(bug)was quite large.