(....)
First of all, this is risk management and money management. The second is probably unsystematic play. Let me make a reservation that I do not mean casinos, as well as people playing "for fun". I mean sports betting.
So, how much did your mistakes cost? Did they cause you a serious psychological blow? What were your mistakes, did you learn from these mistakes and do you apply this knowledge in practice now? Were these mistakes simply painful, dramatic or catastrophic?
For me, when I started in sports gambling - Dota2 and NBA, I lost too much money, it's 2 months of my paycheck in just less than a month. What were my huge losses in sports gambling before, which I have already learned that I don't need to lose that much money in gambling. After that, I learned my lesson to have self-control.