there are clearly a group of teams that have superior management: Steelers, Ravens, Patriots. There is a consistency to them where if they are bad, they arent bad for long. You get the sense that they know what they are looking for in coaches and players.
then there are a group of teams that cant seem to get out of their own way: Jets, Bears, Raiders. Lions, Cardinals (sadly). You get the sense things are being picked at random -- and when randomness delivers a good coach (Lions) or a couple good drafts in a row -they win but dont know how to keep it going.