Along with the increasing complexity of any task, the number of possible errors associated with it increases. As a task with many variables, trading has an infinite number of solutions and as many possible errors.
The trader makes trading decisions in conditions of uncertainty, when the confidence in the rightness of one’s decisions can not in any way serve as a criterion for the authenticity of one’s convictions.
Traders constantly make decisions believing in the veracity of their convictions and the rightness of calculations based on them. Not being professionals, regardless of any doubts and differing opinions of others, which may be fully justified, traders will act exactly as they see fit. Their ego does not allow them to change their view on their decisions and forces them to believe in their own rightness, preventing them from thinking objectively.
In practice this problem is solved by dividing the trading department into analysts and traders when the latter cannot make transactions that run counter to the analysis of the former.
An individual trader has to be both analyst and trader, which is not an effective way of profitable trading as the “Statistics of Earning Traders” show. On the market everything seems “clear” up to the point when you open a position and only an unbiased analysis will protect one from the erroneous subjective market opinion that arises from already existing positions or beliefs, which hinder the objective assessment of the situation.