Debunking the Life Point Myth

Heard and read about this alleged "fact" time and time again, but if they didn't matter why is it one of the easiest ways to lose? Besides, it's a direct contradiction as the "pros" use OTK and FTKs to win in minutes. Sure they may seem insignificant at first like when you're paying 5K for Cyber-Stein's effect, but that already leaves you down less than half of what you started with. Then, when you double the ATK of your new Fusion Monster to 8000 or whatever, you're 1 Magic Cylinder away from losing, and that Cyber-Stein is an easy target for big damage on the opponent's next turn. It's realistically a lot like real money. If you're broke, you can't make the plays you need to make to stay alive.