If you've written a powerful book about a woman and your publisher then puts a 'feminine' image on the cover, it 'types' the book.
Next, in importance to books are their titles.
I've never been particularly interested in genre distinctions. They seem to me more useful to a librarian than to a writer.
Kids books Grownup books That's just marketing. Books are books.
Warning stickers on books would be a nightmare.
Genres do exist because frequent users of any large bookstore can instantly tell what any piece of fiction is supposed to be about by its title, its cover and its location in the shop.
Calling a book 'young adult' is only important in that it can help get a book to the right reader. After that, it's a useless abstraction and should be discarded.
Publishers love to compartmentalize, and 'Second Chance' was not an easy novel to define.
I'm just going to write whatever I'm going to write, and whatever shelf or section they end up on at the bookstore is just going to be that, and I'll let the marketing people pull their hair out and worry about it.
I don't like my books being defined by their "about"-ness. So now the subtitle has just become a kind of strap-line on the cover.
I've been typed as historical fiction, historical women's fiction, historical mystery, historical chick lit, historical romance - all for the same book.