“The stock market is the story of cycles and of the human behavior that is responsible for overreactions in both directions.”
– Seth Klarman.
When Warren Buffett famously stated that investing was simple but not easy, he meant that the rules we ought to use in order to make good investment decisions are easy to learn but actually adhering to them is difficult. Disregarding rules while investing cannot be attributed to open rebellion but can be ascribed to the basic human survival instincts that have been ingrained in us since time immemorial. Certain traits favored in the process of Natural Selection and helped our ancestors survive in the jungle actually do not help in the market.