@AC 15:47
Here's another analogy since you like them so much.
Person X was placed as head of security for the main national security of a countries Main Intelligence base. Head of security says to his superiors (which would most likely include the head of national security and head of state) that the security he has put in place is top notch, no-one can get in or break in (as it's guarding such an important asset to said country).
Monday morning, people arrive at the base to work, only to find that there's been a break in. Nothing appears to be stolen, but all files have been accessed.
They later find out, that the new head of security's measures consisted of nothing more than placing a sign on the main gates which read the following:
"All staff and personnel gone home for the weekend, doors are open and alarms disabled, but please don't enter".
- I.E. where's your thirst for blood for the IT security person who allowed McKinnon in?