1) Projecting their own flaws: One of the best ways People who are so scared to admit the existence of their flaws is to deny their existence and reaffirm their self deception by accusing others of having those flaws. I am You know that person who has a certain flaw but always mocks you for having it?
2) Too insecure to see you doing well : Not everybody feels comfortable in his own skin. Some people feel insecure to the extent that they can’t tolerate seeing other people doing things right. By mocking those people and humiliating them the insecure person eases some of his emotional turbulence. It’s a fact that cowards don’t compliment others because they are too afraid to be left behind if people did what they believe they can’t do themselves.(see also How to deal with people who criticize you)
3) Failed to have a useful role in life: In the Solid Self confidence program i said that if a person failed to make significant achievements in life he is very likely to turn to useless victories if he was a coward. While brave people start again and keep trying to achieve their goals cowards go for cheap victories by criticizing any person who seems more successful or happier than them.
4) Very low self esteem: Why do people feel jealous of others? There are many reasons but the most popular one is believing that someone did what they can’t do. Had a person been sure he can make that same achievement his friend did he would have hardly felt jealous of him. Those who have low self esteem feel extremely jealous of people who do things they can’t do and so find no better way to feel good than to mock them or humiliate them
5) Strong feeling of inferiority: We all experience inferiority feelings at some points of our lives but the brave ones of us usually move in directions that helps them ease this inferiority. For example when a brave person finds that he is earning a very low salary compared to his friends he will usually use this inferiority as a motivating force to have a better career. But what if the person was inferior and too insecure to do that? He will just criticize and humiliate people to feel good because he can’t do any better!