Working hard pays.
It gives you a sense of great gratification when that good is achieved. Why? Because it's in our nature to attempt more difficult things than before. Why would Neal Armstrong have any urge to go to the moon for the first time? Why would Derek Jeter have written a paper in third grade about becoming a shortstop for the Yankees?
It's just in our nature. And while some are more persistent than others in their goals, all can be reached with time.