You're assuming that the goal is to be objective. That's not always the case, and even when it is there are often overriding objectives.

Two examples are Mike Wilbon complaining that they should "let the players play in the fourth quarter", and Jon Gruden wanting to get rid of video entirely. Jon wants it to be a human game played and officiated by humans, with all the error that entails. See also limits on coaches challenges to keep the game from being bogged down.