Have you ever fought or sparred with someone who caught you with a technique that you knew was coming and you couldn't stop it? Why does it work over and over again? Because the deliverer of this technique believes in it. Becoming good a a few things gives you the ability to do this. In previous posts, I've talked about being a jack of all trades and master of none. I'm not saying that you should learn new things. But, you should always come back to the basics.