I don't find risking money apart from gambling as a financial mistake because the money we spend will be for some purpose. Even if it was spent on a movie, it's like we've enjoyed the movie time. If it was spent on some business, even if it goes as a failure, I don't find it to be a mistake because of the skills and the efforts in it. At the same time, if the amount is being spent on gambling, much dependency is upon the luck. If we aren't lucky we'll lose, and there is no big work involved as the dependence is on luck. When we are termed to be responsible gamblers, we spend with limitations, but human minds always want more. So, we can't be sure that a gambler won't get triggered after a big win.