Milo's answer has a sweet reason to it....I vote for it.

My bro couldn't come up with anything, except the probability factor (without Milum's added touch of leaving the A switch in the UP position until one prisoner made his fifth visit to the room).

Is there really a semantics problem with you/you all? No one prisoner is going to want to speak out and find himself the only one thrown to the 'gators; but none but the hardendest of criminals (which they all might be, granted!) would want to proclaim a death sentence on everyone, himself included, either. Yes?