Most people think that they can "earn back" after losing money, but they ignore a basic mathematical fact: losses fall linearly, and the return on investment rises exponentially. If you lose 10%, you only need to make 11%; If you lose 50%, you need to double; A loss of 70% would require a 233% gain to return to square one – not counting the consumption of time, psychology and market opportunities. Therefore, what really determines the life and death of trading is never a short break or a lack of profit, but whether to make a loss expand into a disaster.