Some coaches believed they could judge a player's performance simply by watching it. In this they were deeply mistaken. The naked eye was an inadequate tool for learning what you needed to know to evaluate baseball players and baseball games. Think about it. One absolutely cannot tell, by watching, the difference between a .300 hitter and a .275 hitter. The difference is one hit every two weeks. The difference between a good hitter and an average hitter is simply not visible-it is a matter of record