My guess is she was allowed more leeway into what material made the final draft as she got more money. She was able to ignore her editor more.
See, I was under the opposite impression. Her first book was more-or-less straight from the heart because she just cooked it up in her spare time. This was a hail mary shot with nothing riding on it but one woman's dream of becoming a published author. It got picked up for a limited release, caught fire, and she was catapulted into popularity as a result.
But then subsequent books came with bigger advances, more resources, a stricter release schedule, and a publisher that actually gave a shit about the end product. So she likely got assigned a writing coach and a slew of editors. The writing quality improved notably across 1, 2, and 3. The book probably got sampled by a marketing team. The publisher started talking about merchandising of particular characters. Also, she had to do promo tours and book readings and speaking engagements of her own, which cuts into the time dedicated to actually producing the fiction. So I'm sure by book 3 or 4 she had ghostwriters submitting samples and character arcs and the like. And the size of the books grew accordingly.
Also she started responding to criticism more, like how people started asking why couldn’t the characters simply use the time turners all the time. So in book 5 Harry & friends accidentally bump into a shelf of time turners and break them all.
Book 5 was also the point at which "What Harry Potter character is going to die?!" became a hot topic. And just to tease the reader, the story was choke full of near-death experiences for the B-list cast. It was very obviously written with the expectation that bits of the final draft would leak, a thing you only need to worry about if the book is passing through a bunch of different hands before hitting the shelves.
See, I was under the opposite impression. Her first book was more-or-less straight from the heart because she just cooked it up in her spare time. This was a hail mary shot with nothing riding on it but one woman's dream of becoming a published author. It got picked up for a limited release, caught fire, and she was catapulted into popularity as a result.
But then subsequent books came with bigger advances, more resources, a stricter release schedule, and a publisher that actually gave a shit about the end product. So she likely got assigned a writing coach and a slew of editors. The writing quality improved notably across 1, 2, and 3. The book probably got sampled by a marketing team. The publisher started talking about merchandising of particular characters. Also, she had to do promo tours and book readings and speaking engagements of her own, which cuts into the time dedicated to actually producing the fiction. So I'm sure by book 3 or 4 she had ghostwriters submitting samples and character arcs and the like. And the size of the books grew accordingly.
Book 5 was also the point at which "What Harry Potter character is going to die?!" became a hot topic. And just to tease the reader, the story was choke full of near-death experiences for the B-list cast. It was very obviously written with the expectation that bits of the final draft would leak, a thing you only need to worry about if the book is passing through a bunch of different hands before hitting the shelves.