Like look at football for example. There's a reason the Patriots and Steelers have essentially both been good for the last 20 years. They have no salary advantage. Pittsburgh isn't exactly a gigantic market.
They're both superior run franchises to dross like the Bills and the Browns, to use examples from each team's division.
The Bills and Browns constantly miss on their draft picks. They constantly lose trades. They constantly bring in the wrong talent. They constantly hire the wrong coaches.
This happens in every sport.
The Patriots have Brady. As much as I hate them, hes just so damn good. Hes willing to take less too because he wants to win, so they can afford more talent around him (something I wish Aaron Rodgers would have done).
The thing with those teams is consistency, like you said. They dont have a ton of turnover in coaching and that stuff. Teams like the Bills and Browns tend to give new coaches 2 or maybe 3 years, and when theyre still losing they bring in a new guy, and are always in a state of rebuild. Itd be nice to see one or both of them have some prolonged success again. Cant imagine how pissed Cleveland people are that their team suddenly became good when they moved to Baltimore.
Brady isnt good. Bellicheck is god however, (and willing to do literally anything to win, rules be damned). And Brady took less money because he is paid under the table. Which is ALSO against the rules, but Bill doesnt give a fuck obviously.