The ego lives through comparison. How you are seen by others is often how you see yourself.
When I criticise or condemn another it makes me feel bigger, more superior. These are egoic patterns that are often hard to break. Most of the time, the things that bother us about other people are actually reflections of your our internal issues, which is why they are so apparent to us. At times when you find yourself criticising others, ask, “what is it in me that needs to change?”
First we must become aware of these mental processes, and then we slowly drop them.