The feet are a complex tangle of muscle, bones, tendons, and nerves. They doesn't respond to increases in stress as well a muscle would. Bones and tendons can need months or even years to build up the strength to handle the stress of serious running barefoot. People who try this should ease into it slowly. Like over weeks or preferably, months.
I can see how it would be really easy for someone who was actively running when they got the shoes to just go do their normal routine the first day they wore them and utterly destroy something.
I tried to take up running last year. I bought a pair of Vivo Barefoot shoes, and thought they were great. Since I was just starting out I couldn't go more than a few hundred yards without taking breaks to walk. I eventually worked my way up to about 5 miles with a few moderate hills in the route, and never had any trouble with pain or injury.
I never grew to enjoy running however, it was always a chore and while I was doing it my mind was always racing with thoughts of other things I could be getting done if I wasn't running. I didn't feel any better, I didn't have more energy during the day, and I didn't sleep any better, so eventually I stopped.
I still like and wear the shoes, though.