I'd say the #1 reason you don't see coaches rehired right away is buyouts. they make too much money NOT to coach.
Also there are coaches who have the good sense to move on from their current gig before they completely wear out their welcome. Urban Meyer comes to mind.
This HAS to be the year that we beat either UF or Bama on our home field. If UT goes 9-3 but it cant win one of those games, I'm not sure I can be satisfied with the season. We need to begin beating these two teams regularly now.
I'd need to see data that backs that up. Lots of coaches get second chances. Maybe not at D1 level immediately, but almost always eventually unless you are a real dumb@ss like Dooley. Even Butch will get another job once he's done mooching off UT.