I am my own farrier, and I would take the time to make sure the horse was confident before I ever touched his feet. It's about proper preparation.
It is taking months to get AZ comfortable with his feet being touched. When our farrier comes, all I have to do at this point to help calm him, is hold his lip. I don't even have to twitch it anymore, but we did for the first couple of farrier visits. Obviously we're still working on him, but if we waiting for his confidence level to be high enough before getting his feet done, he would be lame from long toes.