Why you keep losing money with trading?

How can one be called a qualified trader?

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

How to determine whether your trading style is short-term or long-term?

How to understand the phrase "the simpler the trading system, the better"?

What is the degree of simplicity here? Or the simplicity here is not what I thought, just use a few indicators, so what do you think of this sentence?

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