because of the way we are taught) never learn how to read efficiently. The mind can move so much faster than the typical reader can read, consequently, reading is boring and becomes a chore because the mind gets distracted because the eyes and lips (yes, there are some folks to mouth the words as they read them) are moving so slowly.
The absolute most valuable class I ever took at BYU was speed reading. Sure, I'll never be an Evelyn Woods Reading Dynamics speed champion, but I can now read a book and not fall asleep - even 35-40 years after taking that class.