Your chosen martial art was built around a central concept.
The core of karate (according to Grandmaster Richard Kim) is the fist.
The heart of Tae Kwon Do (according to the father of Tae Kwon Do, General Choi) is the kick
The foundation to aikido (according to its founder, Morihei Ueshiba) is the tenkan.
So take note that when practicing and learning the various aspects of your chosen martial art, give a little more attention to the art's core, for the art was built on that concept.