I've spoken before, as have many others, about prostitutes' complete lack of business sense.
You would think that they would regard £5 spent on the green light as money well spent, a solid investment that would bring them in more business.
Nope - most of them don't, and no green light definitely does NOT mean that a girl is not working that day
just that she's too short-sighted and tight-fisted to spend a fiver......