If you are not familiar with horses and hoof anatomy, the act of hammering nails into a horse’s foot looks like it causes pain. In one way, this is correct, but only if it is not done by a farrier trained in the job...
So do horseshoes hurt horses? The simple answer is no. If done correctly, a shoe causes no pain. Not all horses need shoes, but it is important to avoid the extreme mentality of never using them...