Why did they choose to open the envelopes?
This was the least realistic thing to me. Two minutes under water is pretty bad, but I can't fathom I would have picked an unknown torture over that.
Considering the first guy DIED, the second guy lost an eye, and the third girl lived and was not maimed by choosing the water, why did any of these people choose to open the envelope? Not one instance was choosing the envelope a good move.
What would you have chosen?