Why do baseball managers wear wrist watches?

Answer 1

The MLB prohibits players and coaches from wearing various electronic communication devices, such as Fitbits and smart watches, on the field during games. So they can track the timing of the game and Other gadgets are allowed too.

Answer 2

Baseball managers wear wrist watches so that they can know how much time is left during a turn. Each team usually gets a chance to play as defense in one play and as the offense in a different play.