This is Exactly What You Want to See on the Back of Your Hotel Room Door
We often gripe about housekeeping barging in on us, even though we've put out the Do Not Disturb sign. We've also been concerned about intruders breaking down our door (the likelihood is low but still) so when we saw this on the back of the door at The Bellagio we got excited. You know, in a hotel nerd way.
The hotel door has both a door lock (turn the handle up like in the photo) as well as a latch. Double the protection. It's especially useful when you're stalling in the room after check-out time. Not that we've ever done that or anything. Nooooooo. Not us.