The reasons behind the development of narcissism are complicated, and there are many factors that contribute to it. But two of the most common pathologies are narcissistic indulgence and the narcissistic wound. Most people who suffer from narcissism have one or both of these. Everyone has some narcissistic tendencies - it's part of having healthy self-esteem. If you didn't have any narcissism, you wouldn't have the confidence to do what you need to do to achieve your goals in life. After all, you have to believe in yourself and your abilities if you're going to be successful. So a little narcissism is actually a good thing.