Optimism bias

As humans, we are programmed to assume our solutions will work. It is an important evolutionary trait. The military solution to this optimism bias is to assert deductive reasoning and the arrangement of a reserve capacity, to compensate when systems fail, resources run out, or solutions are exhausted…..

~ Rob Johnson

Comment: The equivalent for investors, to maintaining a reserve capacity, is position-sizing: never bet so much on any one trade that an adverse outcome, or string of adverse outcomes, would affect your ability to keep investing/trading.