It doesn’t matter what we want.

Once we get what we want, we vy for something else. Our needs cannot be satisfied; they only enlarge. Suffice to say, if you don't achieve something, the world doesn't end. There's always something else you can aim for. That's what humans do.

Fulfillment

A happy life is a fulfilled life. A fulfilled life consists not only of cherishing joyous occasions, but mastering the obstacles. A sense of achievement is necessary to feel happy. You can only feel it when you have achieved something by overcoming your troubles.