Media perspective really drives coaches longevity...
Cowher, for instance... wasnt beloved by a lot of media guys... he was gruff and short with them and didnt cater to them... at the start of 2004 there was a growing clamor to fire him among the press... tge narrative was that he had missed the playoffs in 4 of the past six years at that point
Bear in mind that he made the playoffs his first six years, and three of those were afc cg trips with one super bowl loss... and that the down years were not really as bad as the press made it out to be.
After a really good start in 98, the injuries caught up with them they went from 5-2 to 7-4, then lost their final five games for cowjers first losing season. Lack of depth killed them in 99 as well... losing 7 of tgeir final 8 games, but by 00, tge team was rebuilt. That team started 0-3 but went 9-4 from that point. You could clearly see the foundation of the super bowl team starting to show...
2001 was fantastic, and added another AFCCG, 2002 ended on a BS call... 2003 was just a fluky, injury prone season... so the reality was Cowher has a 24 game stretch over 3 years while he rebuilt the 90's blitzburgh group into the 00's soon to be championship squad.
So we have a ton of early success, a rebuild phase, and then more success with one isolated injury driven bad season