I read this quote today: “A picture book must have lots of potential for illustration. If nothing much changes visually in the story, then it may not be a good fit for a picture book. My first editor at Dutton once said in an interview that she knows a story has potential when she starts seeing the images in her head as she reads the story.” — Kim Norman
in Institute Transcript, ttp://www.institutechildrenslit.com/rx/tr01/kimnorman.shtml
I think the same thing holds true for writing novels: good writers create scenes that can be imagined in the reader’s mind. Follow the link if you’d like to read more.