I think deliberately inducing a degree of what the psychologists call learned helplessness is a part of it. If you continually stress out a rat randomly in ways

I think deliberately inducing a degree of what the psychologists call learned helplessness is a part of it. If you continually stress out a rat randomly in ways out of his control, the rat will fail to take advantage of escape opportunities. It will helplessly sit there and put up with the random shocks (or whatever) even when the door is open. These firms absolutely want the employees stressed out to a degree that contemplating escape from the cage seems like too much.