some people always think that - when you will start gambling -you will only win and gain profits and money.
but you are right - its not always a win - there are losses as well. And that's not a reliable passive income. One should look for another opportunities for the passive income.
To be sincere, this is just an understatement, not that not all the time is a win, for anyone that is gambling to make money, most time will be for loss, the person will gamble, win and lose, but having net profit of losses which makes it losses for the person. Only what will later happen is that the person will sell his property to gamble and become a problem for him.