PMD is a catch-all term for basically anything done to a coin after it leaves the mint. They do not add value. For common date / current coins, it's just a spendable face value item.
Rarity and value come from acts within the mint done by the mint machinery somewhat in the ordinary course of events.
Only with rare coins does
PMD not largely/completely erase the numismatic value.
-----Burton
50+ year / Life / Emeritus
ANA member (joined 12/1/1973)
Life member: Numismatics International, CONECA
Member: TNA, FtWCC, NETCC, EveryCountry (online) coin club
Owned by three cats and a wife of 40+ years (joined 1983)
Author: 3rd Edition of the Sample Slabs book,
https://www.sampleslabs.info/