Martinfail is never recommended to players, but those who are new in gambling and think they can outsmart the casino by methods written on the internet which have constraints that cannot be fulfilled in reality. They forget that the casino is running for years and have been making profits for many years too from the players who lose more than win.
Martingale doesn't always fail though and I am living proof of that. It's a useless strategy in the long-term and will suck up your bankroll quickly, but it's actually pretty effective in the short-term if you play smartly.
Any strategy can be effective once. Even if you bet your entire balance with 0.5% win chance there is still a possibility of winning that 1 time. That doesn't mean you played smartly it just means you got lucky and got an improbable result. Even with zero house edge there is no smart way to use martingale. If you're a whale you might go bust less often and if you set stop loss targets you can avoid losing all your funds but long losing streaks still occur regardless of how low the house advantage is.