There's "no unauthorized personnel", and then there's "Fire door, alarm will sound".
In college, i worked at a university recreation center, and the desk I worked at was about 15 feet from a fire door. It sat somewhat between the weight room and the men's locker room, so virtually all male customers walked past this specific, well marked, fire door during their visit. And about 2-3 times a week, while I was working, somebody would finish up their workout and just push that door open and walk out. And every time, they'd look thunderstruck that the alarm did in fact sound.
I eventually dropped all pretense of understanding that they were on autopilot, and began commenting as I deactivated and reactivated the alarm AGAIN "I thought universities required students be able to read". Only one person ever got short with me over that, and all I had to do was point at the letters that were bigger than their head, directly at eye level, 18 inches from their face, while they pushed the door open.