Just because OP doesn’t like it doesn’t mean it doesn’t exist, nor does it change the question of what to do when they don’t have said indicators. All OP asked was “why don’t they have indicators.” These are reasons why. The other reasons are greed and laziness.
Try to open it. If it doesn’t open it’s in use.
Which brings us back to the initial question.
You can also usually see feet under the door since there’s like 5 feet of space between the floor and the bottom of the door…
That’s an american thing
Which brings us back to the initial post:
Just because OP doesn’t like it doesn’t mean it doesn’t exist, nor does it change the question of what to do when they don’t have said indicators. All OP asked was “why don’t they have indicators.” These are reasons why. The other reasons are greed and laziness.
Come on, it doesn’t help anybody to suggest the things they say they don’t want to do.
“I want to do X without Y”
“Have you tried Y?”
It’s just a completely useless suggestion.
You don’t have to peak under or knock, just try to open it. If it doesn’t open don’t bang or rattle it just walk away.
“Why don’t toilet stalls have indicators?”
“Just try to open them”
Yeah, that’s also not a useful suggestion, even less the second time around.