The earlier version of this was a bunch of stamps, but it got unwieldly so they trained people to use a stick. You can still see some of the hints of this. I found a piece showing some of the evolution. https://omniglot.com/writing/sumerian.htm…
It still astounds me that this was ever developed because it’s so complex. I wonder if some scribe ever said “This is bull&$*t, why I can’t I just scratch something simpler with a sharp stick.”