Purgatory is a pedagogical stand-in for reincarnation. Think about it: a place where you’re not bereft of God’s presence, but must suffer in order to be cleansed of your sins – possibly for a very long time. Does that sound like this world? Yep. Furthermore, suffering requires not only consciousness, which entails embodiment, but self-consciousness, which entails embodiment as an intelligent creature. So it’s pretty clear that Purgatory is a covert reference to rebirth as a human being. Besides, the RCC had no official document denying reincarnation until the 1992 catechism (sic).
But the intentions were good. The RCC introduced the notion of “purgatory” to deal with the problem that the laity thought of reincarnation as “not a bad option at all, since plenty of fun can be had in the world”. To address that misguided perception, the notion of reincarnation was eliminated from the RCC theology. But that created a new problem: if there’s no reincarnation, does that mean we go straight to heaven or hell? Clearly that didn’t work, so a stand-in concept was offered that emphasized further purifying suffering: Purgatory.
But there’s a problem: while Purgatory can conceptually replace future reincarnations, it fails to cover previous reincarnations. That’s why the RC theology now has the clumsy notion that a freshly created soul joins a freshly conceived embryo in the womb, thus giving the impression that a soul is something that has a beginning (at conception) but no end (for it will ultimately attain unto Heaven or Hell). This is an impossible asymmetry.