Here's the backstory...
I Live In the Facebook™ Ads Manager
Or, At Least It Seems That Way Sometimes
Once FB added the Audience Insights area, it was awesome!
The problem was, it would kick up, what I thought, was a goldmine but when I'd bring them over to the Ads side of things, they'd just disappear.
They weren't available to advertise to.
So, I got to work with the long, arduous process of getting Facebook™ ads API approval so I could see what was really going on.
The story is simple and it follows the old adage: necessity is the mother of all invention.