Many investors have been losing money in stock markets due to their inability to control emotions, particularly fear and greed. In a bull market, the lure of quick wealth is difficult to resist. Greed augments when investors hear stories of fabulous returns being made in the stock market in a short period of time. "This leads them to speculate, buy shares of unknown companies or create heavy positions in the futures segment without really understanding the risks involved.
Instead of creating wealth, these investors thus burn their fingers very badly the moment the sentiment in the market reverses. In a bear market, on the other hand, investors panic and sell their shares at rock-bottom prices. Thus, fear and greed are the worst emotions to feel when investing, and it is better not to be guided by them.