The biggest factor why traders lose money is impatience and greed, I have noticed that many new traders must have trades open, they want to see them running and making money, they feel that if no trades are open they are losing money, the reality is quite the opposite.
New Manual Traders Love The Thrill Risk Taking
Most new traders who start out treat it like a game, they must have positions open so that they can get their fix of emotions from losing to winning, their emotions get negative when they lose and they get caught in a vortex of self-destruction.
Traders Who Use Automated Systems
I have found that most new traders who use an automated trading system are disappointed if the robot does not open many trades per day, so they can also watch the trades and get their adrenaline going, having many trades open with a technical trading strategy is doomed to failure. There are some trading strategies that are designed for many trades being open, but most systems run on technical analysis.
A vast majority of automated trading robots use technical indicators together with support and resistance levels, this means there are periods of stagnation (no trading), this can be very frustrating to impatient and thrill-seeking traders and they enter a trade anyway, this will usually lose them money.
Each position you open incurs a commision and spread fee.
More trades = more risk
The bottom line is that you should only enter a trade when you have a high chance of winning