Barefoot running is best learned during the preseason when fitness is a lesser concern. Unless you are already regularly barefooted, the progression toward appreciable distance takes weeks for some, and months for others.
I consider running in a novel way, but one that's as natural to humans as are the undulations of flying to sparrows, and swimming to elephant seals. That means regardless of medium, on this planet, horizontal locomotion requires us to hitch a ride with gravity.
Because the running shoe materially alters natural gait and simultaneously robs us of the feedback necessary to correct and adjust our faulty stride, this protective, supportive device creates and becomes itself a threatening environment.
Shoe companies and health care providers have traditionally put forth that various levels of biomechanical shortcomings are the root cause of our locomotive problems. We are inherently flawed, and only cleverly-designed footwear is the solution.
We spend most of our waking day in shoes. We put on dress shoes in the morning for work, then switch to running shoes for workouts in the gym. With so much time spent in shoes, we've come to expect not only style, but also comfort in footwear.
We've still got those same feet, but we don't use them anymore. Instead, we cover them up. We wear shoes that alter the structure and function of our feet, and that weaken the myriad tendons, muscles, and ligaments through disuse.