Your conscious mind can't handle all the calculations needed to reach a goal. You decide what you want, then your subconscious takes over to execute it. Running fast shows this: you choose the goal, your body figures out the muscles and movement.
There's so many calculations involved in getting what you want, you can't consciously keep up. Imagine trying to consciously run as fast as you can. Lift my leg up, I'm gonna extend it, I'm gonna— you gonna be the slowest runner out there. You use the conscious mind to decide to run fast as you can, but after you make the decision, you get out of the way and let the subconscious mind move the muscles and the ligaments and the legs. You let the subconscious mind run that part of the show.
