But if we consider gambling just a luck game (98% luck game), any strategy will lead us to the bankrrupcy, no?
Martingale or any other method you use to bet, sooner or later you will lose your balance, on long term it's impossible to beat the house. Sometimes one or another gambler claims to win on long term, but I'm not really sure about this.
The fact is you cannot measure your luck and you cannot even determine when it will stay when you feel you are lucky, when luck comes to us we should know that it's only temporary and that is why sometimes we win if we are discipline too. Martingale is a from of bankroll management and like any other forms, it will not help you to win but your ability to select games and predict it right most of the time will.
you don't need to measure your luck to be able to win. you just need to be lucky and have luck on your side.
and in martingale system you can never have luck on your side because you are playing against the house with a house edge and that means the edge is giving your luck to the house instead and makes them win specially in the long run.