Did you know the coin-op classic Gauntlet only came about because one of the game's creators, Ed Logg, was being bugged by his son, a D&D fan, to make a game set in that universe? During a postmortem of the first four-player arcade game at this year's GDC, Logg, a designer on Gauntlet, talked about building the game that was once upon a time simply called "Dungeon," and designing a concept around a problem—in this case, the struggling arcade industry of the mid-80's.
So here's what the arcade business was like back in 1985, according to Logg: on average, arcade owners would take in a quarter for every 90-180 seconds of play, and they'd effectively reached a ceiling in how much money they were able to bring in from their games. And while the idea of 50 cent games was on the table, it seemed like everyone on all sides was kind of squeamish about trying to milk an extra quarter from kids at arcades.
Enter: Gauntlet in what Logg describes as a "eureka" moment for the industry. The top-down dungeon crawler was a four-player game at 25 cents a pop, meaning the machines would be taking in a dollar for one to two minutes of play. Plus, players could come and go at any time, and the jump-in nature of the game meant that there was no dead time, in spite of the marketing team's fear that gamers would be unwilling to play with strangers. Apparently, this wasn't a problem, because Gauntlet was a hit and the (in)direct inspiration for later four-player co-op titles in arcades like The Simpsons and Teenage Mutant Ninja Turtles.
As for Logg, this wasn't the first major success for the designer: he was also in part responsible for early arcade classics Centipede and Asteroids.