Marketed at a demographic of twelve to eighteen-year-olds, some critics believe adults should be embarrassed to read novels aimed at adolescents.
In some people's opinions, young adult novels often feature idealized romance, trope characters, lazy storytelling, and overdone themes. One critic goes as far as saying 90% of young adult novels are crap.
Another critic believes young adult fiction is becoming dull and uninspired through its simplified prose. They criticized writers who simplify narrative, claiming it underestimates the intelligence of teenage readers and that they deserve better. 
Children's writer Geraldine McCaughrean echoes this sentiment. During her 2018 Carnegie CLIP awards speech, McCaughrean spoke out about censorship of vocabulary in young adult novels .
McCaughrean, backed by the librarians on the Carnegie judging panel, argued stories with rich language and complex themes are vital in helping children develop their understanding of the world .
These proponents believe most young adult fiction is not good enough for its demographic, least of all adult readers.