Back when I was a lender (15+/- years ago), I could swear that I read somewhere official that, at least at that time, it meant Member, Appraisal Institute. I am aware that this has been disavowed as an acronym, but I don't get why--how would the fact that the letters represent an acronym 'dilute' the brand? If not an acronym, then why M, A, and I? The A I is so obvious that it belies their contention, so why then M? Why not some other random letter?
I can imagine someone not especially familiar seeing the letters following a name on a business card and asking: "what's that?" It seems more suitable to me to be able to say "It stands for . . . blank, blank blank" . . . "and what's that?" . . . "it's a professional designation for Real Estate Appraisers"
than . . .
"What's that?" . . . "A professional designation for Real Estate Appraisers" "What's it stand for?" "Well, nothing really"
Make it an acronym for something -- Member, Master, Mondo, Mega -- something.