It is perhaps possible for a book to be an entertaining one and yet not a very good one. I have found this to be the case with The Inheritance Series, Artemis Fowl, Maximum Ride and several other substandard YA novels (perhaps including The Hunger Games) though they each differ in quality. And again they could be considered good writing on the one level that they convey their intended plots to their target audience (after all why else would they be selling millions and possess a large fan base - perhaps a fan base without much sense of the better quality fiction available but a large fan base no less).
This certainly appears to be the case with The Rise of Nine
which is far more entertaining than its predecessor novels with an increase in action, superpowered heroics and a lessening of the romantic triangle focus in previous novels. Yet that said it remains, in an aesthetic sense, poorly written and therefore no great novel. Yet it was a passable novel to read when feeling a little under the weather or wanting an escapist YA action novel.
I will never be able to love this series because of 1)the writing, 2)the authors involved in writing the books and 3)because it's rather simplistic despite being entertaining. Yet the completist in me feels compelled to keep reading and finishing these novels for the sake of it...