"Follow" is hard to follow. Do ya follow?

When I said I wanted to follow someone, I repeatedly got a vague error message that there was a problem, and I should refresh the page. I kept doing it, same error message, over and over. But I guess the person did get my follow request. Or maybe not. Maybe it was because I had invited them and the invitation was pending - maybe that creates a problem. So people have to accept the follow request, is that it? I don't quite get this.