Why do most traders lose and wash out of the markets? Emotional and thoughtless trading are two reasons, but there is another. Markets are actually set up so that most traders must lose money.
The trading industry kills traders with commissions and slippage. Most amateurs cannot believe this, just as medieval peasants could not believe that tiny invisible germs could kill them. If you ignore slippage and deal with a broker who charges high commissions, you are acting like a peasant who drinks from a communal pool during a cholera epidemic.
You pay commissions for entering and exiting trades. slippage is the difference between the price at which you place your order and the price at which it gets filled. When you place a limit order, it is filled at your price or not at all. When you feel eager to enter or exit the market and give a market order, it is often filled at a worse price than prevailed when you placed it.
The trading industry keeps draining huge amounts of money from the markets. Exchanges, regulators, brokers, and advisers live off the markets while generations of traders keep washing out. Markets need a fresh supply of losers just as builders of the ancient pyramids of Egypt needed a fresh supply of slaves. Losers bring money into the markets, which is necessary for the prosperity of the trading industry.
– Alexander Elder, Trading for a Living