Actually, that's generalizing. There are a lot of good authors, as well as some real stinkers. This is true, not only about the U.S., but all over the world. In fiction, it boils down to two things.....the writer's imagination, and the ability to tell a story in an interesting fashion. Some are very good at it, others not. Even in non-fiction, the ability to explain things in a lucd fashion is very important. Isaac Asimov and Robert Forward were geniuses at this.