Everyone has a dream. Nobody wants to give the control of his/her dreams to anyone else as dream can be one of the most important things in people's life.
We also want to be a great person, contributing to making the world a better place. However, what makes a person great? I want to be a scientist, but I can't due to my personality and IQ level. I want to be a superstar but I can't because I don't have the necessary qualities. It's not who you want to be but who you can be makes you different.
Furthermore, who you can be depends on who you want to be. So dream big, start working on what you want to be until it turns to what you can be.
Protect your dream until the rainbow shows.