The shape of Latin S arises from Greek Σ by dropping just one out of your 4 strokes of that letter. The (angular) S-condition made up of a few strokes existed to be a variant of the four-stroke letter Σ presently while in the epigraphy of Western Greek alphabets, as https://andytkaqf.theisblog.com/31504700/what-does-bud-naked-concentrate-mean