"Sore" feet after a trim?

We had a farrier at one point who my horse hated, and my horse's feet (barefoot at the time) were usually very sore afterwards. The same farrier had trimmed or shod (he had shoes for awhile) my horse since before I bought him and had never had this problem with him--so I'm not sure why things changed. None of our other horses were ever sore. I moved my horse and used a different farrier (who has both trimmed him barefoot and put shoes on him) and my horse has yet to take a lame step, even being ridden the same day. What gets me is that the farrier who caused him to be sore is a very heavily used farrier around here; he had worked on all our horses for years and we had never had a problem. He worked on our trainer's horses, which is where he started working on mine, and had no problems. He had always done great work. But when my horse immediately became sound after trimming when a different farrier did it, it became obvious that something was going on.