If you're not failing every now and again, it's a sign you're not doing anything very innovative.
Failure is more frequently from want of energy than want of capital.
FAILURE, ENERGY THAN WANT OF CAPITAL
Failure is not our only punishment for laziness there is also the success of others.
FAILURE, FAILURE IS NOT OUR ONLY PUNISHMENT FOR LAZINESS
Failure is instructive. The person who really thinks learns quite as much from his failures as from his successes.
FAILURE, FAILURE IS INTRUCTIVE
Failure is simply a few errors in judgment, repeated every day.
FAILURE, FEW ERRORS IN JUDGEMENT