People like doing what they are good at and avoid doing things that they are not so good at. It’s an ego thing: nobody likes looking like an idiot, and once martial artists get good at something they tend to stick with it.
The tendency to specialize isn’t necessarily bad thing – in fact it is essential to improving – but don’t get so caught up on improving your strengths that you ignore your weaknesses. Your fastest progress may come from working your weakest link. As in so many things, my inspiration here is Dan Inosanto. The protégé of Bruce Lee and a black belt in many martial arts (including BJJ), he is always the first to tie on a white belt and try something that he is not good at. He loves learning new material, and is not put off by the possibility of looking like a beginner.
Weak links come in many forms. Your weak link could be
-Takedowns (drill takedowns for a few minutes after every class)
-Endurance (start working your cardio)
-Pin escapes (let your training partners start with you pinned)
-Flexibility (do yoga)
-Armlocks (don’t allow yourself any submission except armlocks)
-Strength (lift weights)
Don’t be a slave to your ego and stay in your comfort zone all the time. If you are honest with yourself you can figure out what is holding you back – be strong enough to put on the white belt, acknowledge your weak link, and do something about it.