Many times when people talk about the relationship between success and personality types, one of the themes that gets trumpeted over and over is how different people who have completely opposite personality types can become successful. They'll contrast Donald Trump's extroverted personality against Bill Gates' introverted style. The reason why this is possible is because most people who become successful do it by building an organization of people around them. Therefore, they are able to fill in their own "personality holes" by hiring people who have a personality profiles that complement their own. For example, people who are visionary thinkers generally see the end product but don't care about the process of how things will get done. But the "how" is a very important factor. Hence, these visionaries hire people who are detail-oriented to meet the "personality needs" of the business.
The problem with investing, though, is that it is a solitary activity. This means you can't rely on the strengths of others to make up for your shortcomings. In my opinion, this explains why successful trading is considered to be one of the hardest endevours one can attempt - because traders can't simply "outsource" the required personality traits that they don't have. In these cases, traders have to do something that is inifinitely more difficult - change themselves. Changing your own behavior is probably the single hardest thing one can do in life. And I'm not talking about simple behavioral habits like remembering to leave the toilet seat down. I'm talking about the kind of change that requires you to alter your natural mindset and personality makeup. Because changing yourself is something most people are incapable of doing, this means that if there is a personality characteristic that is required to be successful as a trader and you don't have it, then you will probably fail.