It's always too early to quit.
To know oneself, one should assert oneself.
Know or listen to those who know.
Problems are not stop signs, they are guidelines.
I can, therefore I am.
By failing to prepare, you are preparing to fail.
Who seeks shall find.
To be a good loser is to learn how to win.
Without hard work, nothing grows but weeds.
If you've got a talent, protect it.
It's too bad that one has to conceive of sports as being the only arena where risks are, for all of life is risk exercise. That's the only way to live more freely, and more interestingly.