Psychology plays about 80% of successful trading (as noted by Van Tharp). However, character and personality can help. Often these are skills that can be learned. And where did i get this? My biggest source of evidence: SPORTS. The best of the best practice and practice time and time again until they are world class. A chap called Malcom Gladwell studied the art of success, amongst other findings, he concluded that you needed to complete 10,000 hrs practicing, and learning before you can be world class. So to be a successful trader is matter of hard work, constant practice and 10,000 relenting hours of market analysis and actual trading. Bottom line, trading is tough, you have to put in the work to build character, decipline and all those special characteristics.