I hated this. I started school in Saxony (state in Germany), and then my family relocated to Bavaria. The curriculum switched from a science to a language focus, so I already knew all the next-level Chemistry, and was really annoyed by the style of teaching it wrongly.
I (in NZ) remember that happening in physics and chemistry, but not maths. Maths has unambiguously and provably correct answers, so while more general methods and topics are introduced, old results don't change. (Maybe this is why I became a mathematician!)
This pattern appeared in my math math education in the USA as well, but not as pronounced as in physics or chem. The biggest example is that we were initially taught that you cannot take the square root of a negative number. I also have vague memories of learning that a larger number cannot be subtracted from a smaller number (sometime early in grade school).
Then the next year they'd do it again.
We'd occasionally catch them at it when in Chemistry they'd tell us electrons worked one way and in Physics they'd say they worked another.
Anyway, I can definitely see how an enquiring mind might want to move past all this and find out The Truth.