I used to be the buyer for a video and game rental store. Before people corrupted the meaning of the phrase, it had to do with investment potential. Yes, exactly like how "AAA" is used in financial matters.
I used to get catalogs from major wholesale video and game distributors (oddly, there is a porn distributor that still sends me catalogs). Many of the games were rated with AAA, AA, etc. It was a way for retailers who didn't know much about gaming to select key releases with a high ROI.
It had absolutely nothing to do with how much a game cost to make but instead with how much a game was projected to earn.
It's kind of funny now to see people calling big budget flops AAA. I remember specifically some 3DS titles being rated AAA. I remember Pokemon being AAA and, I'm pretty sure, Kirby. It wasn't rare to see games like Cooking Mama rate an AAA, as well.
So, yeah, this is really a case where people who didn't know what a term really meant creating their own definition and then everyone else repeating it as gospel until it effectively replaced the original definition.
I believe this story.
On topic: What is AAA? What is AA? What is A? Where is the line?
To those who say that prodiction costs are the difference: how big need those be to be considered AAA? What is high, what is middle, what is low?
Is it rather in relationship to something? If so, to what? And most of all, how do we even know what costed how much? There are no numbers
anywhere, so how can we think we could categorize anything?
We can't. We lack the most basic thing: the numbers. We can only make educated guesses based on
a) how the game looks. This doesn't mean anything as we still don't know how much the middleware costed, how long the core production went on,
how much time was spent during concept phase, how many working hours were needed for prgramming, how much each developer receives as a
salary, how much it costed to outsurce specific issues - we don't know shit.
b) this sad list: https://en.wikipedia.org/wiki/List_of_most_expensive_video_games_to_develop. Sad because it's in no way expansive or reliable.
It may only be a reference for very vague extrapolations based on nothing.
So after all, we can only project what each of us believes this ambiguous term is supposed to mean. Personally, I believe it's nothing but a marketing
term which has the intention to make me think that a game is supposed to be of high quality. Like a premium product. The more As the better.
Production values do not matter in this regard, it's all just a fancy dancy glitter shitter term. But that's just me. I am very cautios when someone tries
to sell me something, anyway.
BUT: this term actually serves as a categorization system for those who don't know much about a game and need some sort of relation to other games.
So basically, it serves the exact same purpose like it did back in the days in Pokokos story. It's a shining star for the unknowing to make them feel less
insecure about their purchase.