[Kelvin Ng]

Perhaps if you demonstrate the accuracy at which balls can be shot, they would be convinced.

You can also point out that scoring in the corner goals will be giving them balls to load for their robots. If your opponents have a strong firing robot, scoring in the corner goals may just give that robot extra ammunition. I agree rolling is not satisfactory for this game. If your team is worried about accuracy, give your robot the ability to recover balls, so the balls you miss may be retrieved =).