Proper money management, the very important tool to keep you safe from your gambling activities.
Like what you have said, there's no assurance using martingale the losing streak is unpredictable, most of the time frutrations hits
you up and leads you up to make wrong decisions, you'll find yourself losing control and lose every single cents of your bankroll.
The one who understand risk and have a good setup plan mostly exit the house with a decent earnings.
Money management is key but we must admit that it is kind of difficult to do on the heat of the moment, precisely because of this we must never deposit on the casino more than what we are willing to lose on each session, if you do that then you are going to protect yourself from making a mistake in the case you get mad for losing many times in a row, now many do not like to do this especially when the fees are very high since this increases their costs but you can use altcoins during that time so you can use this strategy successfully.