This weekend Rollo told me, “No more pedicures!” In his language it sounded like this, “RRRAArrrr!!” and involved fancy spinning and a bit of mouth work. I’ve done his toenails twice and front feet a third time with no incident but he was increasingly tense as I tried to snip his back nails. I’ve never nicked him but am not surprised.
Years ago I had a rescue pit that had clear nails and never nicked him either but over several trimmings ‘ol Wally developed enough of an exception to it to start nipping me. I suspect, even without getting nicked, the experience is unpleasant for them.