RO question

[lapince]

hi all, I would like to understand something that I have seen many times and that I cannot explain to myself, this watch seems to be in good condition, according to them never polished, but on the third pic on the bottom of the case especially on the side where the number is the metal seems completely worn out, how the hell is that possible, we're talking about a part of the watch which when is worn can't have any contact dings, scratches or bumps, how in the hell can it get so worn out?

I've had a few watches for many years, even one or 2 for around 20 years, well on that part they are fine, but on the outer part they have their fair share of scratches, the exact contrary to this one and I've seen it in many occasions and never could get how that's possible, anyone care to explain would be welcomed.

Thanks guys

https://www.chrono24.com/en/audemars...-id3748687.htm