Full-on Narcissistic Personality Disorder is relatively rare (only 6.2 percent of the population), but narcissistic traits are seen often in individuals. Have you met that person who is only interested in themselves, is patronizing, a know-it-all, or has no empathy for others?
The Huffington Post online posted an article in April about a 21 year old woman in Australia who hit a cyclist with her car while she was texting. She was apparently very upset because her car was dented, but she had no sympathy for the cyclist who's spine she fractured. This type of behavior is not only disgusting, but also dangerous.
Be interested, not interesting.