why does one volleyball player wear a different color

One volleyball player wears a different color jersey because that player is called the "libero," a defensive specialist with a unique role and different rules than the rest of the team. The contrasting jersey helps referees easily identify the libero to enforce the specific restrictions of the position, such as only playing in the back row and not being allowed to serve, block, or spike the ball from the front row. The libero position, introduced internationally in 1998, allows for more defensive specialization and longer rallies. This player can substitute in and out of the game without counting against the team's regular substitution limits, so the distinct jersey makes it easier to keep track of them during play. The libero's main job is to strengthen the team's defense and passing, but they cannot participate in front-row attacking actions.