[solopilot]

Robots can specialize in each zone.
In the near zone, robots can push the ball into the goals AND steal balls from opponent.
In the middle zone, robots can recover returned balls and feed them to robot in the near zone.
In the far zone, robots can recover returned balls that roll thru the tunnel AND block goals by the opponent in that zone.

The only reason I can think of for the robot in the near zone to change zones is to elevate itself; it can't use the tower that is closest to it.