I think that some books are more successful than others to certain readers. People who read my books for the humor, they’re going to love one book. People who read my books for the mystery, they might not like that book quite as much.

Evanovich is pointing to the variability of reader expectations and how genre-blending affects reception. Her novels—especially those mixing comedy, romance, and mystery—invite different “entry points”: one reader may prioritize laugh-out-loud character comedy while another wants tightly engineered suspense. The quote suggests that a book’s “success” is not absolute but relational, depending on what a reader comes seeking. It also implies an authorial awareness that shifting emphasis (more humor in one installment, more mystery in another) can delight one segment of an audience while disappointing another, without either reaction being a definitive verdict on quality.