About "Profit and Loss Share the Same Source": Making money and losing money follow the same logic

After trading for a long time, I increasingly agree with one principle: profit and loss share the same source.
What does it mean?
The logic that makes you money, under a different market environment, is also the reason you lose money.
A few examples:
🔸 Trend-following strategy
When the trend is there, make big profits.
In choppy markets, repeatedly stop-loss, losing until you doubt life.
🔸 Mean reversion strategy
When the price deviates, wait for it to come back, earning from the correction.
But in a trending market, the more you add, the more you lose, eventually leading to liquidation.
🔸 High leverage strategy
When the market is right, returns double.
When the market is wrong, the principal is wiped out.
My realization:
You can't only accept the good of a strategy and reject the bad.
A strategy cannot make money in all market environments.
Knowing when it will lose money is just as important as knowing when it will make money.
Accepting "Profit and Loss Share the Same Source" means:
Not dismissing a strategy easily because of drawdowns.
Nor becoming overconfident just because it makes money.
Maintain a calm mind, accept the imperfection of strategies.
Have you ever given up on a strategy because of losses, only to find it made money later? #btc