Understanding it or figuring out where it came from would be even worse than killing it. The characters knowing almost nothing except what they observe directly is what makes it so terrifying.

It also functioned well as a metaphor for growing up/loss of innocence. I'm not sure how well it will go trying to explore that theme further using the same metaphor.

They didn’t even get through an entire movie without ruining that mystique. It wasn’t very “unstoppable and inevitable” when it was just standing on the roof of a house, or when it just grabbed that girl by the hair but failed to do any damage.

Until it happens to befall a depressed or suicidal person who just goes "fuck it" and let's it catch up. What then? The curse cannot be passed on so it's essentially just over forever, right?