What exactly is the "nerve damage" that acupuncture can cause?

Nerve damage: Acupuncture does not cause nerve damage. Rumors of nerve damage are a myth.

Should be none: Acupuncture needles are not stuck into nerves so there should be no nerve damage.

Uncommon: Needles are to be placed in close proximity to acupuncture points so as to contact the electric field (or qi). Needles are not to be placed in nerves. It would be possible for a sloppy needler to rapidly insert a needle into a nerve which would cause inflammation and thus injure the nerve. This does not happen often (if it did people would be very reluctant to see the acupuncturist back).