Revealing mistake: When Strahm's phone says "no signal" there is actually a three bar signal. (00:06:35)
Revealing mistake: When Stahm is in the cube trap, there is one shot just before he sees his phone, gun, etc. and you can see a massive gap down the side of the cube where it wasn't shut properly. With the size of the hole, it would be extremely hard to keep water in the cube. (00:09:35)
Revealing mistake: When Strahm removes his jacket at the end of the movie and starts pushing the walls with his hands and uses his legs, when he takes his feet off the wall, the wall moves. Now considering these walls are supposed to be solid steel, this doesn't make sense. The walls are actually wood.
Revealing mistake: When Strahm is being crushed by the "closing walls" at the end, watch closely during the last few seconds. There is a brief shot from above Strahm, looking down as he screams and the camera is spinning. If you watch closely, you can tell the "closing walls" that are crushing him aren't moving during this shot.
Answer: That was the entire point of the trap. Each trap in the overall game was meant for them to all work together. The tape for this trap asks "Who will be the odd man out?" They took this to mean that one person had to remain outside the chambers, but what it really meant was two people would each share a chamber (assuming all five survived the first trap) and one person would occupy the third chamber all by themselves. Charles realised this and tried to tell everyone, but was unfortunately killed by the explosion before he could.
Phaneron ★
Nope actually he said who of you 4 has to die...how he knew was 4 survivors?
He does not say that at all. The exact wording is "With only three points of safety, which of you will be the odd man out?" At no point does the tape say that one of them has to die. That would be completely contradictory to the point that the five of them were supposed to work together to safely get through every trap.
Phaneron ★
Not what he meant. He knows human nature is survival at the expense of someone else. He set the trap so all could survive, but he knows the panic and self-preservation will lead the group to sacrifice someone.
The_Iceman