assumption:
Initial capital 10m.
1st year: you are up 1m (11m in account), taxed at, say 20%
2nd year: you are down 1m. Not taxed.
3rd year: up 1m, taxed at 20%.
4th year: down 1m, not taxed.
And so on.
Eventually, your capital will be less than the 10m initial capital.
You can see that you...