Because the media will present the news? Recipients of the message, unable to know whether it is good or bad, what is correct or not. If the media is not good, or attend a party side.
Because the media presented the news in the side. Subscribers can not know what is good or bad. Is correct or not. If the media does not compromise Or favor any party then.
Because the media is presented in the news? The receiver of the message can't know if that's good or bad. What is correct or not. If the media was not good, or take sides.