Why does a set of numbers always have the same output?

Question

If sets are unordered then why does a set of numbers always have the same output? Meanwhile a set of strings always has a different one

https://sololearn.com/compiler-playground/c9S8544FR49w/?ref=app

Answer 1

I asked the same question before, and the answer has lots of technical details.

https://www.sololearn.com/discuss/3247712/?ref=app