I used to watch a farrier or my old man shoe a horse when I was young, they would let me, under strict supervision do a bit of rasping/knocking in nails, I was fascinated.
The first consideration is the safety, comfort of the horse.
I went to my mates today to see about shooting, he had the farrier there, guess what, I asked if I could have a go, he agreed and it brought back memories, I rasped off flat, shaped the hoof ok but the clipping was not quite good enough, I set one shoe and after he adjusted it I knocked in 6 nails no damage done, I enjoyed it but you do get back ache.
Interesting