Saban like many coaches, and most fans, gets seduced and fall in love with superior athletic ability. They equate this athletic ability they can see, to production, can't miss, kind of importance and at some positions it does have value but at NFL QB position atheletic ability is perhaps the least important asset.
At the NFL QB position in fact superior athletic ability often masks real weaknesses in becoming an effective NFL QB.
A player with superior atheltic ability tends to rely on it rather then doing the hard work it takes to devolope the mental aspects of being a QB, those aspects like, hard work off the field constantly seeking improvment, leadership, focus, making good decisions with the ball, reading defenses, moving around in the pocket and finding the open reciever, rather then tucking the ball and running or worse throwing the ball up for grabs.
The most successful NFL QBs are superior mentally rather then atheleticly. But these mental aspects unlike the atheltic aspects can not be as easily seen or judged.