1) Your Emotions and risk levels cannot be separated
Let’s be realistic, fear is a quick emotional calculation of the odds (a quick assessment of risk, based on emotions.) It is often not mathematically based that leads you to the wrong conclusion.
2) Fear causes predictable behavior
The fear of loss causes you to exit a winning trade too early and hang on to a losing trade to long. You know this is a predictable behavior. So if you recognize that fear is controlling your behavior, you can control that behavior.
3) You like to think you are in control of the market
The only thing you control is your entry and exit order. You have no control over the market.
4) You substitute one trading system for another
Once your system enters a drawdown, you tend to look for another trading system that is doing better. You must remember all trading system will have periods of draw downs. There is no Holy Grail in Trading.