This brings us to the second main objection to robot umps, which is that they would strip away part of the human element of the game. Baseball, like other athletic contests, is a fundamentally human endeavor, in which humans strive for excellence despite their limitations. It may be argued that removing human umpires from strike-zone duties reduces this important element of the sport.
However, the excellence of baseball is found in its test of human athlete against human athlete, within the confines of the rules, equipment, and field. The human element of the game is found in the contest between the pitcher and the batter, not between the players and the umpire’s ability to call the strike zone accurately and consistently.
The strike zone is not meant to move. It is supposed to be static for each player. Just as the bases, pitching rubber, and walls don’t move, neither should the strike zone. There is a reason why “calling balls and strikes” has entered our lexicon as an example of impartial judgment (just ask Chief Justice John Roberts).