Happiness comes down to doing things that are fulfilling and to have a happy life, you need to have a fulfilling life. I read about an interesting principle leading into this theory called Pleasure/Achievement Principle by Chris Skellet.
In order to live a fulfilling life, we must strike a considered balance between pleasure and achievement.
So just filling your life with small and big pleasure is not going to make you happy and fulfilled neither will a life of being the richest person on the planet. One needs to strike a good balance.