One cannot "want" something that he/she can already do for themselves, such as happiness. Happiness cannot be completely "wanted" because it is, for the most part, controlled by the self.
As an example, take the idea that I “want” to study. If the book I am to read for class is not in my body’s vicinity then I am able to “want” for studying since it becomes something “out-of-grasp” for me; however, if that same book is directly in front of me then it is not a “want” for study because it is a certainty that I can. All I must do is open the book and begin. To “want” something that one is certainly able to do for oneself is a lie to oneself. If the book I “want” to study is directly in front of me then I am lying to myself of such “want” because I merely stare at the book.
With happiness: If one “wants” happiness then they are presenting themselves with at least a partial lie because happiness is up to the individual. I can make myself happy, I can be happy by my own means. I do not “want” happiness because I am, for the most part, in control of it.