In the mid 90s I spent some time playing football and training at the University of Nebraska. I was in awe at how the football program generated such an advantage under Tom Osborne. You walked the hallways next to the locker room and you see each year's roster, record, stats... 10-2 was an off year.
Some of the things I noticed:
the weight room was state of the art. And they were well ahead of the curve on powerlifting (after you clean, deadlift, and squat you can clean, deadlift, and squat), they had nutrition coaches (remember this was mid90s), everything was perfect
they had two indoor facilities that rivaled pro teams
their stadium field was "different". What I mean is it was thin, sharp astroturf, laid on a bed of concrete. When coach said "take a knee" that was the most painful part of the day - your knee had cuts on it. The hardness took a while to get used to. Can't imagine being the visiting team. To top that off they had tons of speed at the skill positions, which made them even quicker.
they ran the option. High schools during that era weren't passing so they had a recruiting advantage.
Tom Osborne had started "advanced metrics" and each player was graded on several criteria. I remember having a great practice (DE) and asked the D-Line coach what I graded out for quickness and he gave me a 4 out of 5... with 5 being the worst. I'm like damn coach I thought I dominated. He says, "You got the only 4."
Tom also took care of his athletes. I remember seeing all these big guys painting the steps of the stadium. Well on one side they painted the steps, the other side they stripped the paint off. The best job was turning on the lights and turning them off (they paid the guys the entire time the lights were on).
So I give you some reasons Nebraska dominated for 25+ years. I would like to know why Notre Dame became Notre Dame in college football. What gave them a recruiting advantage, what made their program great before it was great?