Self-control is the biggest and most important thing in gambling. Someone who has no self-control, gambles more after losing, because after losing they become very emotional and have false confidence in themselves, they think that they will definitely win the next games. But instead of winning, they suffered more losses.
Losing in a game against an opponent causes anger, paying for the loss lifts frustrations on players. Too many times gamblers would feel someone is an enemy that needs to be won in gaming, so the self control goes unnoticed at such a state of mind. Although it's reprehensible that gamblers think in this way, and regrettable that most of them smother in an air tight cage of poverty, following gambling as a competition is the real purpose behind the loss of control, because nobody feels comfortable with failure.