No, it is not literal as far as returning to the starting point. But actually a "loop" in English can also mean an arc that is not a complete circle, but enough of a circle to make you think of a circle. I am thinking as an example a "loop" of film from the old-style film-projectors. The "loop" would be pulled around different rollers, and travel in an arc, or several arcs, but would not return to the starting point. So when I hear this expression it means to me that some information is traveling in a set path from one person to another.