I believe, the Ancient Greeks and the Romans brought into forefront the phenomenal "S" curve. It is related to and is an extension of the art term "contrapposto": when a figure is portrayed as slouching it shifts the center of gravity to one side. The body and posture is painted like a sinuous or serpentine "S". Richard Macdonald, the celebrated figurative artist is prolific with the "S" curves. He drives and rides on "S" curves. He is the inspiration behind this thought phenomena.
"S" curves are used in abundance in trade show booth designs and in architectural spaces. In your next photo shoot use the imaginary "S" curve to compose a fluid story line.