Saw, in one panel

As more than one reviewer, professional and blog alike, has observed, as the Saw films go on, for the plots to work, you have to believe that Jigsaw can correctly predict what anyone is going to do at any given time.

And that he can do so far in advance, given that most of his traps tend to take just a little time to set up. Unless you happen to have handy, say, a device that both gouges people's eyes out and tears off their limbs.

So, this...



...this would explain a lot.