From Theodore Roosevelt…

It is not the critic who counts, nor the man who points out how the strong man stumbled, or where the doer of the deed 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 short again and again, because there is no effort without error and shortcoming, who does actually strive to do the deeds, who knows the great enthusiasms and spends himself in a worthy cause, who at best, knows in the end the triumph of high achievement, and at worst, if he fails, at least fails with daring greatly.  His place shall never be with those cold and timid souls who knew neither victory nor defeat.