You can't dream up ...

You can't dream up confidence. Confidence is born of demonstrated ability.
 Bill Parcells

Quotes from the same author

I have always felt like you really don't have a genuine confidence unless you demonstrate the ability to do something. You can talk about it, but you have to demonstrate it.
 Bill Parcells
The only players I hurt with my words are the ones who have an inflated opinion of their ability.
 Bill Parcells
Confidence is only born out of one thing ­ demonstrated ability. It is not born of anything else. You cannot dream up confidence. You cannot fabricate it. You cannot wish it. You have to accomplish it.
 Bill Parcells
Any penalty - I've told you a hundred times - can be eliminated by concentration or good judgment.
 Bill Parcells
I don't like celebrity quarterbacks. We don't need those. We need battlefield commanders.
 Bill Parcells