"The most important comparative advantage that a manager or trader should have is a thorough appreciation of the need to have a comparative advantage. Traders who do not understand why comparative advantage is important will not consider whether they have a comparative advantage before they trade. If they do not consider this question, they can have no reason to expect that they will trade profitably. " (Larry Harris, 2003) What is your comparative advantage? This does not mean a tested method or self- discipline. It means to know against whom you are trading, and why he/she is going to lose against you, even if he/she/them also have a tested method and self-discipline.