Just who is this aimed at? Under what conditions would I (or anyone) be reading this sign, from outside, while the red light is flashing? Is there some chance that someone qualified to be standing outside this door, while the light is flashing, someone with an understanding of how to open the door, wouldn’t also know when not to do so?
I’m sure there are perfectly reasonable answers to those questions. But as someone boarding a plane about to soar above the Pacific ocean, I gotta say I found them somewhat unsettling.