To add to this, there's a misleading phenomenon that first occurs where the performance actually gets worse with too much data/parameters/epochs, but oddly improves again if you throw even more at the model.
https://openai.com/blog/deep-double-descent/
https://www.lesswrong.com/posts/FRv7ryoqtvSuqBxuT/understand...
(Edit: Oh, the definition appears in the abstract of the linked paper.)