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My usual trading system continues to fail, what should I do?

If a trading system built by myself often fails and causes losses, should I abandon this system and replace it with another one? Is there a stable and profitable trading system?

I have been unable to set the stop loss in the transaction, how can I do a good stop loss?

If you want to make money in trading, what principles do you need to understand?

If you have a bad mentality, does this mean that you are not suitable for trading?

As a "trader", what trading discipline do you have to restrain yourself?