One thing the conversation seems to be missing is rocks and handling.

Rocks are mostly an off-piste issue, but I have seen it happen on piste. Especially early and last season when cover can be low. Will occasionally also happen near the lift when a spot gets warn low. When I get rock gashes, it's always easier to just send them to the shop's machine.

Handling also introduces a fair amount of nicks. In theory, the edges should never meet at an awkward angle, but it happens. Skis slide around on the rack, skis flip out a position while carrying them, things shift in the car, etc, etc.