If you're going to gamble, do it for entertainment, not for profit.
It's a fallacy to believe you can actually make money/profit off gambling. The odds are always against you, especially when betting against the house.
The problem with some gamblers is that they believe that gambling can make them rich. Yeah, maybe it will but you need to spend a lot of money.
Some gamblers are gambling just for fun only or stress reliever but some are doing it for profit which is bad.
Maybe if they want to get that from their thick skull, they need to go do research on finding the number of people who could come out openly to say gambling has made them extremely wealthy in a short period of time. I can bet my last satoshi, that just very few would come out to say so and that leaves the larger percentage in losses.
The best practice is to know that you are not up for any get rich system in gambling and if you cannot deal with that and just simply focus on enjoying your game while gambling with what you can afford to lose, then, it is better not to even be gambling at all.