I had the opportunity to be involved with world's atleast two most well known and practiced martial arts - Karate and WingChun. I did Shotokan Karate where my goal was to have a black belt which demonstrates a mastery on an art or a new phase of learning which ever way you wanna see it. On the other hand I wore black pants and shirt during our Wingchun practice and the goal was to get white shirts as we progress. The choice of colors and it's relation to ones progress has strong bonds with it's traditions. In Karate, where the color white corresponds to nascency or a blank slate which will get the color of knowledge, black relates to the color of maturity where all colors eventually meet - a state of empowerment. Wingchun starts with black showing a state of darkness or no knowledge and white the color of light which brings an ability to see i.e, to gain knowledge and understand the truth. Two completely opposite traditions and the way of learning, but the goal remains the same - to achieve an ability to understand the truth. The ultimate goal is not to defeat an enemy in a combat but to avoid the combat itself. The goal is peace and harmony which Yoga has taught us for thousands of years and has filtered out in the various forms of martial arts practiced today. So the color does matter or may be totally irrelevent depending on the goal of your chosen path to the ultimate truth.