They should actually hope they do not ever achieve their dreams. Because they would likely find that the contentment and happiness they were hoping to get does not materialize. In fact, they end up feeling worse. Because not only will they find they do not feel more content or happier, but that they have also lost the illusion that 'if only' they had this or that that their condition would improve. They discover that what they have been experiencing is, in fact, the human condition.