Whether it is foreign exchange or stock market, the psychology of traders is an important factor affecting this market, and this factor cannot be quantified; "Buy low and sell high" is a slang term that we often mention in the transaction process, which is very different in itself; In addition, the experience of mature traders is also important.

There will also be many burrs or "noises" in the process of price calculation, and these factors will be used by computers as effective signals. At the same time, once the market direction changes, the computer does not change in real time, but continues to operate according to the original instructions, and its loss is also very huge.

Therefore, many traders do not directly use automatic "EA" in the trading process, but choose semi-automatic settings and join the manual screening mechanism. Coupled with a stable and mature trader screening mechanism, the probability of automatically adding positions due to trend changes is greatly reduced.