Life has a tendency to provide a person with what they need in order to grow. Our beliefs, what we value in life, provide the roadmap for the type of life that we experience. A period of personal unhappiness reveals that our values are misplaced and we are on the wrong path. Unless a person changes their values and ideas, they will continue to experience discontentment.
Given the opportunity of 'Earth-School' enrollment - some are humble enough to learn and grow, stubborn enough to fail and repeat, and wise enough to graduate and never return.