Gambling outcomes are unpredictable, so you won't expect for a long-term winning, but bigger wins and smaller amount of losses can be undeniably achieved through having self-control and discipline. The problem is, majority of the gamblers fail to have self-control over greed, but that's just normal for a human being. Eventually, when you have gained more gambling experiences and being exposed to different scenarios, that's when you'll learn the natural way of gaining self-control.