This is the same with "gambling must only be for fun and never for serious matters". Must agree.
People should really treat gambling that way.
I mean gambling is not something that people should be serious unless you have the ability or skill to be a professional. It doesn't mean that you can win games by yourself, which means that you can also be a professional.
Every gambling games have different levels when it comes to entertainment, and they just have one trigger, that is when you gamble for fun but you win a very big amount of money out of the blue and that's what makes you think you could pull it through when you are going to be serious about it, then it goes and on and on and on, until you found yourself in a hole where could couldn't even fit yourself but still you are insisting to fit in just to convince yourself you could win big again in the future if you keep on trying, and you don't.