If a contestant was rejected after their first audition, why didn't the judges remind them they could audition again the next year?This approach would decrease every disagreement and confrontation between the judges and the contestant, and even between the judges themselves.
The judges should always sit up straight and maintain eye contact with the contestants because these facial and body gesture will maintain the level of professionalism which the show is centered around.
Why did the producers and writers hire Ellen DeGeneres to serve as a judge for the fifteenth season? She has no experience in singing and the music industry. While other reality TV competition shows compete in all forms of entertainment, American Idol is limited only to singing.
Even though the judges know its unprofessional to argue with each other in front of the contestants, the show partially depends on conflict and controversy, it's what sells and creates interest, hence Simon's insulting comments.