Most traders do not make money in the markets over the long-run for one simple reason: they trade way too much. One curious fact of trading is that most traders do very well on demo accounts, but then when they start trading real money they do horribly. The reason for this is that in demo trading there is virtually no emotion involved since your real money is not on the line. So, this goes to show that emotion is the #1 destroyer of trading success. Traders who over-trade are operating purely on emotion.
Trading when your pre-defined trading edge is not actually present is over-trading. Trading if you have no trading plan or have not mastered a trading edge yet is over-trading. Essentially, you need to know EXACTLY what you’re looking for in the market and then ONLY trade when your edge is present. Trading too much causes you to rack up transaction costs (spreads or commissions), and it also causes you to lose money a lot faster since you are purely gambling in the market. You need to take a calm and calculated approached to the market, not a drunken-gamblers approach…which seems to be the favored approach of many traders.