I heard these stories of people who totally changed their lives by gambling but I wonder how many keep the money they earned.
I don't believe that gambling can change their life in quotes. Gambling is only to measure luck and to entertain oneself. Sometimes I also feel strange about the stories told by people that gambling can give them something that can change their lives. What is meant by change may not be how much money is earned, but how much money is used up or changes from rich to poor.
there are many stories like that where somebody wins big and it changes their life, but you're right on thinking this is not the most common situation
neither something we should rely on when choosing a life path