At one point or another, everyone who has interactions with the market asks oneself, “Why is trading so hard?” There are legitimate reasons why trading should be difficult: markets are highly random; whatever edge we can find is eroded by competition from smart, well-capitalized traders; some traders work within various constraints; and markets are subject to very large shocks that can have devastating effects on unprepared traders. Even so, it seems like something else is going on, almost like we are our own worst enemies at times. What is it about markets that encourages people to do exactly the wrong thing at the wrong time, and why do many of the behaviors that serve us so well in other situations actually work against us in the market?

Part of the answer lies in the nature of the market itself. What we call “the market” is actually the end result of the interactions of thousands of traders across the gamut of size, holding period, and intent. Each trader is constantly trying to gain an advantage over the others; market behavior is the sum of all of this activity, reflecting both the rational analysis and the psychological reactions of all participants. This creates an environment that has basically evolved to encourage individual traders to make mistakes. That is an important point—the market is essentially designed to cause traders to do the wrong thing at the wrong time. The market turns our cognitive tools and psychological quirks against us, making us our own enemy in the marketplace. It is not so much that the market is against us; it is that the market sets us against ourselves.