Casters are both the housing mechanism inside the leg of a piece of furniture and the wheel to which it is attached. Casters allow a piece to be moved with care and ease. That’s just a definition. By evidence in my home, I clearly have a thing for casters.
Did I experience the 360° round settee from my own experience (a large hotel lobby?) Or, from old B&W movies on late night television? Nonetheless, a circular settee holds a place in my primitive design brain as being quite glamourous.