While scanning my morning news headlines I came across the Scientific American article headline
"Quantum Particles Aren’t Spinning.
So Where Does Their Spin Come From?"
Quantum Particles Aren't Spinning. So Where Does Their Spin Come From? - Scientific American
Personally, I would apply my vast intellect and venture to say "Nowhere" since they "Aren't spinning"

"Pauli, in an attempt to explain the structure of atomic spectra and the periodic table, had recently postulated that electrons had a “two-valuedness not describable classically.”But Pauli hadn’t said what physical property of the electron his new value corresponded to, and Goudsmit and Uhlenbeck wondered what it could be. "
So I guess it could be said that Goudsmit and Uhlenbeck questioned the truthiness of Pauli's statement.

Anyway, an interesting article with a deceptive title . that should read
Quantum Particles Aren’t Spinning.
So Where Does Their angular momentum Come From?

If the quote "Better to remain silent and be thought ignorant than to speak and to remove all doubt, " is true then perhaps I should have kept my mouth shut, at least on this and some other subjects . LOL