Let's stop making money and fame the only measure for success. Being successful is being happy and satisfied with ones fully achieved dreams. Money cannot buy satisfaction and happiness. Satisfaction and happiness is the true definition of success and anyone without this can not be declare as being successful.
I think success or happiness is the definition of each of our thoughts. there is someone who feels himself successful because he has a lot of money. but on the other hand there is someone who feels successful when he has his own business (not much money). and happiness will appear after they feel successful in their own way.
It's true that money can't buy happiness. but (not hypocrites/losers) everyone will be happy when holding more money than before. How can one be happy without money? because when a person has more money they will surely be able to buy whatever he wants and feel happy and successful in that moment. I very rarely see someone can be happy without money while in his heart thinking about buying food tomorrow
so my conclusion :
someone will feel successful and happy with the definition of his own thinking or in his own way and supported by the money in his pocket