It constrains the Narcissist and limits him. It is often prohibitive and inhibitive. As a result, the Narcissist is afraid to do certain things. He is injured or humiliated when forced to engage in certain activities. He reacts with rage when the mental edifice supporting his disorder is subjected to scrutiny and criticism - no matter how benign.
Narcissism is ridiculous.
Narcissists are pompous, grandiose, repulsive and contradictory. There is a serious mismatch between who they really are and what they really achieved - and how they feel about themselves. The perception of his superiority is ingrained in him, it is a part of his every mental cell, an all-pervasive sensation, an instinct and a drive. He feels that he is entitled to special treatment and to outstanding consideration because he is such a unique specimen. He knows this to be true - the same way one knows that one is surrounded by air.