There will be a time when you need to choose between "What is Right" & "What you Want." If you choose what you want may not be right and also what is right you may not want to have. Choosing any is one of the most difficult situation you may face in your life.
Similarly, both may have different impact in the short run as well as in the long run. You choose what you want may adversely affect now but may benefit in the near future and the vice-versa may hold true for choosing What is Right.
That's why there is a saying, "Follow your Heart but take your Brain with You."