They are unhappy when they detect an unfulfilled desire within them. They work hard to fulfill this desire, in the belief that on fulfilling it, they will gain satisfaction. The problem, though, is that once they fulfill a desire for something, they adapt to its presence in their life and as a result stop desiring it—or at any rate, don’t find it as desirable as they once did. They end up just as dissatisfied as they were before fulfilling the desire.
