Major League Baseball (MLB) currently schedules many 3 game series between teams, which allows teams to play more games against divisional rivals and less against non-divisional opponents. However, many are wondering why MLB doesn't schedule more 4 game series. The primary reason is that the league would have to add an additional off day for teams, which could lead to longer road trips, more injuries due to increased travel, and an increased risk of rainouts. Additionally, teams are hesitant to add an extra off day due to the fact that it would reduce the amount of revenue generated from ticket and concession sales. Finally, teams are also worried about the effect it would have on the current divisional structure, as some teams would benefit more from 4 game series than others.