> mfg came from manufacturing; its existence meant that some people started using it for manufacturer as well; but having a g in the abbreviation without one in the word bothered people, so they added an r to make it mfgr.
This leads me to wish there was a well-researched blog for abbreviation/initialism/acronym etymologies, the way https://grammarphobia.com/ is for English word etmologies. But I guess there aren't that many of these that are in need of explanation; usually they're pretty obvious.
Something that always amuses me is that the two-letter abbreviation for Shanghai is SH. I find this funny because it seems so natural from an English perspective.
In fact, of course, nobody cares what English speakers think about a Chinese abbreviation of a Chinese name, and the H in the abbreviation refers to the second H in the word, not the first.
For MAC addresses (also mfgr-allocated) mistakes like this are “fine”, because MAC addresses are layer-2 (switch-local) and therefore a collision will translate to a direct, customer-visible problem: they’ll buy two of the same device, and then their LAN will start acting wonky. As such, market forces will address dumb Ethernet equipment mfgrs, pushing them out of the market as customers stop buying them.
But the people buying cellular handsets aren’t the same people running the network, so there are no market forces in play to push back against dumb handset mfgrs. Instead, the network operators must just play with the hand they’re dealt; and that means coming up with alternative strategies for managing handset connectivity that don’t involve the theoretical primary key (IMEI) but instead make use of other unique keys (e.g. IMSI) that are also included in the connection handshake.