Why does everyone seem to hate Piper Mclean?

To clarify, I don't mean everyone, and I don't mean hate. I mean that a lot of people seem to dislike her for some reason. I read the Percy Jackson books since I can remember. I can only remember reading Percy jackson and Harry Potter. Recently, I've undergoine a nostalgia wave including me finishing both PJO, HOO, ToA, Magnus Chase and the Kane Chronicles and the entire HP series in like 3 weeks. I was just wondering why Piper is so disliked.

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Edit 1: OMG this blew up!!! I was just curious, and I opened up reddit after a day of CAD work and I was not expecting this. Thanks for the upvotes!