I have a secret to tell you. I don't think The Photograph is the best novel ever written. I don't think it's the best contemporary young adult novel that will be published in 2014 or June of 2014. I do think The Photograph is a great novel for a specific group of readers–my target audience. The Photograph is targeted towards girls ages 12-16, specifically athletic girls. The teenagers who fit that demographic are much more likely to enjoy the book than other readers. For instance, the novel has an element of mystery and intrigue in it which may attract readers not in my target audience. If you are a 33 year old man, you may still read and like The Photograph, but the chances are much lower.
As an author, it is important to know who your readers are for each book. The writing in my Zelda books is different than The Photograph which is different than the current project targeted towards an older YA audience. You can't write for every reader. It doesn't work. Plus, the target audience also affects your marketing and promotions. Let me give an example.
My Zelda books have a unique audience. Reading level wise, they are targeted for students in grades 3-5 (ages 7-11), specifically kids who like dogs. However, the secondary target audience is pug owners of all ages and demographics. People love their pugs and love anything to do with a pug, so they buy Zelda books. So in addition to Author Day presentations at elementary schools, I also market Zelda through ##pugchat on twitter (it's a thing) and will be selling books at Pug Fair in September (also a real thing).