The Steelers of the 80s looked exactly like the Panthers of the 00s, and Cowher took over and they started winning regularly and immediately.
The Patriots were winners before Belichick got there, it's arguable that they started winning under Parcells, and he also started winning in his second year there.
There just aren't any good examples of people who did it with this "build a winner over time" mentality. Good coaches just about always start winning right out of the gate. Coaches who put together multiple winning seasons in a row just about always do. I've looked, and I can't find an example in modern era football where a coach built a streak of those multiple winning seasons and wasn't winning by year two.
Maybe you can help me out there? I can give you a bunch of coaches who won right away for every one you mention.
I think you have to ask a different question. How long did it take for a coach to turn around a team that was decimated of talent, had a poor defense and no franchise quarterback?? Unless a team is going to out and try to buy themselves a better team through free agency, doing through the draft takes time.
I don't think this is a name how many did it in 2 years versus those that didn't, but I think we were a lot like Dallas when Jimmy Johnson took over. He took 3 years to win and in year 4 he won a Super bowl.
He had the good fortune of being able to trade Hershel Walker for a ton of picks to accelerate the process. Still he had to get a franchise QB and train him, build back the offense and defense and establish his system and culture.
I think Rivera is trying to do the same thing without having the advantage of a winning culture which is what Johnson had following Landry. I think we are on the cusp of something very good.
I am sure it just me.................