"S' curve is the age old crux of creative expression.
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.
In the 20th century the S-Curve emerged as a mathematical model and was afterwards applied to a variety of fields including physics, biology and economics. It describes for example the development of the embryo, the diffusion of viruses, the utility gained by people as the number of consumption choices increases, and so forth.
"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.