Everybody uses martingale even when they kept losing it all by applying this method. I use to be doing martingale too. Its effective at first and then losing streak. This is where you really will believe the game is rigged when you have $100 and still lost it all despite when to start with $1. It only takes 7 successive loss and its all gone.
I win more betting on sports than on dice or blackjack without having a technique all just following sports picks of sports gamblers.