Why is waking up early so hard? The reason is because of a phenomenon known as sleep inertia. Every night we fall to sleep, our body goes through four phases. The phase 3 and 4 are the ones where you are in the deepest sleep. There have been numerous inventions such as the face clapper than slaps your face till you are awake enough to slap it back (wicked!) or tilting beds which will simply throw you off the bed. This is another of those things that can be produced and no kidding this will sell in billion units.