Here's an excerpt of an interview from 2002 with Kent Hull about his mental preparedness during his Buffalo Bills career.
"Speaking for myself, I’m not a perfectionist. But I’d like to say if I’m going to get beat I’m not going to get beat mentally. You’re going to beat me physically. The whole time I played I just couldn’t understand how someone could keep making mistakes mentally. It just irritated me so bad, that I don’t think I’d have the patience to coach. I’d wind up being one of these hard-asses that nobody would want to play for because I don’t have any patience for that."
"I had players who played with me who couldn’t stand some of the things I was saying to them because of mental mistakes. You’re going to get beat physically in the game of football. It’s a physical game. But to beat yourself because you’re not thinking is no excuse. I’m not sure I’d have the patience with some of these guys today."
"When Ruben Brown was a rookie, I guess he thought he was so relaxed because I was telling him what to do that he never worried about anything. Then it started irritating me that he wasn’t trying to learn what he was supposed to be doing and he was putting more pressure on me. And Ruben turned it around 100 percent after his rookie year. That’s just an example. Some people take things for granted when it’s a lot easier on everybody else."
"In the old days when we ran that no huddle and those five linemen were there every week, you didn’t have to say hardly anything. You make one call and everybody else knew what you were thinking. We were mentally ready. That’s not to say you’re not going to get beat physically. But at least you were mentally ready to play."