There is nowadays a vast self-justified security "policy" industry, let alone the actual measures, with policy advisers, policy managers, you name it. Inevitably, working separately, they all come up with different standards, different manuals, different training, etc.
It was a London - Dublin day return a few years ago where on the two legs I got "leave your laptop in its bag, don't hold everyone behind you up taking it out by fiddling to take it out" and "take your laptop out of its bag, can't stay in there, don't hold everyone behind you up by leaving it in there". Can't remember which way round the two contradictory policies were.