Okay. Take a look at the 2022 coaching class, since that involves the Saints, and for some added perspective. 6 of the 10 coaches have been fired. Daboll is arguably on the hotseat. O'Connell, Bowles, and McDaniel are having some success and could be setting up for long tenures with their respective teams. I believe out of the 10 coaches, they combine for 3 wins in the postseason so far (1 each; Bowles, Daboll, and Pederson).
You seem to be seriously dismissing just how hard it is for coaches to succeed in the NFL.