Han has spoken about this in interviews, saying that she felt like the teen books she read were mostly about white characters and didn't resonate with her. She wanted to create books that would make other young Asian Americans feel seen and understood.
In addition to representation, Han also wanted to write about universal teenage experiences, like love, friendship, and figuring out your place in the world. She wanted to create books that would be relatable and enjoyable for readers of all backgrounds.
Her debut novel, "The Summer I Turned Pretty," was a success, proving that there was a market for diverse and relatable teen fiction. Since then, Han has gone on to write numerous other popular books, including the "To All the Boys I've Loved Before" series, which was adapted into a successful Netflix movie franchise.
So, in short, Jenny Han started writing teen books because she wanted to create stories that were more representative and relatable for young readers, particularly those who were underrepresented in the genre.