One often hears the term "AAA" thrown around when talking about top production value games and big releases, but where does the term come from? How was it coined and popularized?
The term is based on the academic grading scale of the United States (where "A" is a top mark) or similar letter-based grading scales.
The "triple" aspect is somewhat hyperbolic, mainly intended to demonstrate how much "better" the games in question are relative to others; there are no "BBB" or "AA" or similar intermediary ratings, generally speaking (in part, perhaps, because there's no really solid definition of what it means to be "AAA").
The genesis of the expression can be found, allegedly, in the 90s, when it was bandied about internally by members of the industry.
"Better" is highly subjective, of course, and can often just mean "had a very large budget," especially today.
The term was used at Electronic Arts prior to 1995. While I was a technical director there, I recall first hearing the term used at a meeting where we were discussing sales data with marketing. The context was that--based on sales data--building anything other than AAA games was a bad business move. The "anything other" were referred to as B games, reflecting the movie industry use of "B movies" for low budget films. Although I hadn't heard the term before, it seemed quite natural and everyone understood what it meant. Triple A was associated with high quality and in the game industry high quality was always expensive.
I don't remember the exact numbers, but the data we were looking at showed that of the over 2000 games made during the previous year, only a very small percentage of them were "hits" (e.i. made huge profits). A larger percentage--but not large--broke even or made small profits. The majority lost money. No low or medium budget game was a hit. And very few low budget games broke even or made a small profit. EA and the other big game publishers focused on AAA games after that. . .at least until "Deer Hunter" proved low budget games--in the right market--could make very good profits. The casual mobile game market drove the final nail into the rule of thumb that to make a large profit you had to spend a lot of money.