I only feel good about myself when I see the faults in others
Why does seeing faults in others make you feel good?
It just does.
You shouldn't be mocking other people for their flaws, because everyone has them, including you and me.  Concentrate on your strengths, and find something that makes you feel good and proud of your abilities.
Everyone sees fault in others, what does it matter?
Yes, you're right that we all notice flaws in other people, but it's important to recognize that this is just part of being human.  If you want to feel better about yourself, I still advise that you focus on your strengths rather than on their weaknesses.