There are many other aspects of your personality which can play into your trading. Not every trader excels at using every trading system. You can take ten systems that work (in theory), and ten people who can handle the pressures of trading. If you give each person the system that suits his or her trading personality best, all ten may be profitable. But if you give each person a system that does not suit him or her, all ten may fail. This should tell you a lot about the role of the trader’s psychology. It is one of the core elements of success or failure.