Let's be honest. Chuck'd always envy Saul's social skills and his extroverted personality alongside his great sense of humor. Chuck in the other hand never had friends apart of Howard however he always manipulated him to make him take decisitions to destroy Saul.

He wanted to prove he was better than him by becoming a succesful lawyer and that's why he did everything he could to sabotage Saul's career as a lawyer. Plus, everytime people talked about his brother's skills as a lawyer in front of him he was always shown slightly annoyed because that was the only thing he had to prove himself to be better and superior than Saul.

Do you agree or not? Let me know what you think.