Not entirely true at all ... set reasonable expectations of yourself ... if you're 5'2" and weigh 90 lbs. it's more than a certainty that the NFL is not for you.You can accomplish anything you set your mind to.
Otherwise, drive fast and take chances, just not so often at the behest of others. No risk, generally provides little to no reward in any relevant capacity.
Perfection is unattainable ... don't waste your time
Don't have any fucking kids!