One factor is diversity of options. Only a generation ago if you wanted information you would turn to a book, newspaper, or some other printed media. Now the pe

One factor is diversity of options. Only a generation ago if you wanted information you would turn to a book, newspaper, or some other printed media. Now the people reading newspapers can get faster and better news online. The people reading trashy romance novels can now watch trashy reality tv. The people interested in fiction have plethora of movies, tv, and video games available at a single click. Today reading is something you'll do if you enjoy it, but sitting down with a book is no longer required. As an aside, I think a lot more people are reading regularly than you realize. They just typically aren't sitting on facebook responding to statuses.