Saban wins because he is a joyless perfectionist that is obsessed with winning football games. He might actually be part robot. That and the commitment of his school, and a large portion of the state of Alabama, to ensuring UA stays on top by any means necessary. Auburn can’t rat out UA without ratting themselves out, and tbh they aren’t as good at shady recruiting as UA is.
It was apparent that Fulmer was done as soon as Urban beat him his first two years and Saban was hired at UA shortly after. All things come to an end eventually, Fulmer just didn’t realize it until the wheels had completely come off and it was too late.