By the way, ALL Martingales (and most grids) face the same exact challenge, which is why no Martingale will survive more than a year or two. That ONE day ('Judgement Day') WILL COME.
with the standard casino martingale you have right!
with an async hedged open martingale (brownian motion, probabilty theory) you are wrong!
the most reason why martingale crashes accounts:
-less equity, equity, equity
-use of standard casino martingale
-no knowledge about brownian motion
-no knowledge about stochastic processes
-no knowledge about the different martingale systems, like open, closed, hedged (why most all trader meaning the casino martingale)
-no security features like async hedges
-use of static values for tp,ts,ts,lots - useless in an dynamic market!
-static grids if used...hello, fx is an dynamic market!
and much more
an with 'unlimited' equity, you will survive casino martingale very easy, 9 strikes in a row against you are very rare.
martingale in use with several other features is very stable with less then 20% (m)dd and cant crash your account!