I very much like this quote by educational consultant Nicholas Hobbs; I find it inspiring:
Life is always highly problematic and what you become will rest in no small measure on the kinds of problem situations you get yourself into and have to work yourself out of.
It is exceedingly difficult for a person to take thought and alter the quality and character and direction of his life. However, he can choose the direction he would like his life to take and then put himself deliberately in situations that will require the evolution of himself toward the kind of person he would like to become.
To know a person, it is useful to know what he has done, another way of defining what problems he has solved. It is even more informative, however, to know what he is working on now. For these will define the growing edge of his being. We sometimes think of the well-adjusted person as having very few problems, while in fact, just the opposite is true. When a person is ill or injured or crushed with grief or deeply frightened, the range of concerns become sharply constricted; his problems diminish in scope and quality and complexity.
By contrast, the healthy person, the healthy in body and spirit, is a person faced with many difficulties. He has a lot of problems, many of which he has deliberately chosen with the sure knowledge that in working toward their solution, he will become more the person he would like to be. Part of the art of choosing difficulties is to select those that are indeed just manageable. If the difficulties chosen are too easy life is boring; if they’re too hard, life is self defeating. The trick is to move oneself in the direction of what he would like to become at a level of difficulty close to the edge of his competence. When one achieves this fine tuning of his life, he will know zest and joy and deep fulfillment.