You can't be successful without feeling contentment with what you chose to do with yourself. That's joy. The fact that you are here writing a long response to this shows that you found a joy. Joy doesn't have to be laughing in hysterics. Joy doesn't need to be motivation to doing what everyone else feels is a pleasure. I believe much of this is hogwash. And many are overly judged if they show emotions. They are expected to be numb as if numb is normal and that's what drugs cause is numbness and unalertness. Some people who seem to be dry and numb lacking emotion are the same people who criticize people who have emotional character. Fact is we are not all born as carbon copy clones of each other and that would make this a very lame boring world full of zombies if we all had to be how the heigherachy suggests we are to be think or feel.  You have your joy and perhaps the way you experience your joy isn't what others identify with. You are here doing what you personally enjoy. You are not meant to be the same as others.