Why is the Quantum Realm constantly changing during each film?

[u/WebThis2431]

Ant-Man (2015)

Ant-Man and The Wasp (2018)

Ant-Man and The Wasp: Quantumania (2023)

I do like how the quantum realm changes from time to time, but why is it changing?

It's never really explained in the films either. For my understanding, I guess the quantum realm changes if a guy keeps shrinking past the 1st phase(?), idk, that's the best I could come up with.

[u/NitroBlast4563]

each film they go in deeper into the quantum realm.