Why You Can't Pay Attention?

Every book i ever write, there's a sort of mystery that i want to solve for myself. And for this book, which is called stolen focus, why you can't pay attention? I just noticed that with each year that passed, my own attention was getting much worse. For every one child who has diagnosed with serious attention problems when i was seven years old, there's now a hundred children givin that diagnosis. The average american office worker now focuses on any one task but only three minutes something w has this really always been the case?