One of the top three most requested quotes is that regarding the "man
in the arena" or "not the critic"

"It is not the critic who counts: not the man who points out how the
strong man stumbles or where the doer of deeds could have done better.
The credit belongs to the man who is actually in the arena, whose face
is marred by dust and sweat and blood, who strives valiantly, who errs
and comes up short again and again, because there is no effort without
error or shortcoming, but who knows the great enthusiasms, the great
devotions, who spends himself for a worthy cause; who, at the best,
knows, in the end, the triumph of high achievement, and who, at the
worst, if he fails, at least he fails while daring greatly, so that his
place shall never be with those cold and timid souls who knew neither
victory nor defeat."

Theodore Roosevelt
"Citizenship in a Republic,"
Speech at the Sorbonne, Paris, April 23, 1910