That's because there's no such thing as a secret in gambling that can make a gambler win all the time. Gambling is created to benefit not the gamblers but the owners and the more you spend time playing and gambling the closer you'll get to the house edge and once your near the house edge then it'll be very hard to win anymore. In gambling you have to be wise and have self control to avoid losing more.
Exactly. I've learned the hard way, that there's no secret to gambling. It takes discipline to master skill-based games in order to win most of the times. But the very nature of gambling, implies luck and randomness than anything else. As you've said earlier, gambling games are created to benefit the house than the gambler itself. I believe that you have better chances of earning money by investing directly into the casino's bankroll. It's much better than playing gambling games and losing it all in the long run. While investing in a bankroll is risky, you can still maintain your capital over time.
Still though, if one desires to gamble, then it's highly recommended to never invest more than what you can't afford to lose. Gamble with minuscule amounts of money just to be safe. In luck-based games, there's a higher chance of losing than in skill-based ones. In this case, you can choose to invest a very little amount of money into luck-based games while putting a higher quantity on a skill-based game. Whatever you do, play safe and avoid addiction as much as possible. Just my thoughts