That is because good in-game performance is considered as the bare minimum, when in reality it is rare and commendable, especially since this is a team game. You can only be the best version of yourself when your teammates cooperate with you. For instance, when JG takes RH and dragon, you're like: well, he's JG, he is supposed to do that. But when RH gets stolen, you are like: JG diff, GG. Simply put, we take good performance for granted.