Trading courses and coaches are useless- true or not

As far as I know, many master traders will rely more on the sense of the market, how to cultivate this feeling?

What is a perfect trading system? Or is there a so-called perfect trading system?

How do you view the theory that review is useless?

Seeking expert guidance, what is the difference between left-hand trading and right-hand trading?

How to explain leverage in the forex market?