Sooner or later, they will addicted to gambling. Once that is happen, they will ruin everything they have and even their life.
Each gambling addicted is different. Being gambling addicted isnt something uncurbable and does not mean that everyone will ruin their lives with 100% probability. I think everyone who has tried gambling at least several times are already addicted, because they return to gambling anyway. We have different forms of addiction, someone return and gamble daily, someone on special occasions, someone gamble once each month. But that does not mean we all are moving towards ruining lives.
The more a gambler encounters losses at the casino and feels discouraged while playing, this is one of the possible reasons for him to deposit funds again at the casino and when that happens, he does not notice that he is chasing his losses, but what he thinks is a positive thing where when he bets a large amount, he will recover the losses.
The problem with this mindset is that the gambler becomes more aggressive in gambling because as long as he does not win, he will continue to bet large amounts until he notices
that he has a zero balance on his/her account in the casino.