Room For Misinterpretation

I work in a full-service hotel outside a major US city.

One evening, I check in a guest who, shortly after they get to their room, calls down to request an item be delivered. After confirming they would like the item brought to them as soon as possible, I put in a case for a coworker to deliver said item. 

Ten or so minutes later, my coworker calls me at the desk to say they could not complete the delivery because of a “Do Not Disturb” privacy sign. I call the guest back.

Me: “Good evening, this is [My Name] from the front desk. One of my colleagues will deliver your [item] right away, but they did let me know there is a Do Not Disturb sign on the door.”

Guest: “Oh, did they come already? I didn’t hear any knock.”

Me: “Yes, ma’am, they did not knock because of the privacy sign on the door. Hotel policy is that our staff will not knock when a privacy sign is up unless it’s an emergency.”

Guest: “Oh, I didn’t know! I don’t think I’ve heard of that rule before.”

I confirm the delivery, hang up, and turn to my manager beside me, slightly confused.

Me: “What… did she think the sign did then?”