Diablo III was apparently pegged as an MMO title way back when development first started in 2001. Speaking with IncGamers, Max Schaefer, one of the creators of the Diablo franchise and now founder of Torchlight developer Runic Games, spoke briefly on the matter, saying that they "wanted to make it a bigger game."
"We wanted to make it a bigger game. We were going the MMO route. We wanted to support many more players in the game. When I left the company in 2003 the project was still very early on; far from the point where we could have revealed anything about it publicly, since so much would still have changed," said Schaefer.
"There's lots and lots that goes in inside game companies that never hits the light of day, since projects change so much in their early iterations. We may have changed our own path radically had we kept going on it.
"But at the time our thinking was to go more MMO on it. We wanted to foster big in-game communities. Not just session-based with four or eight people. We wanted more than just 4 or 8 people per game. We wanted a big overworld and a giant shared community."
Schaefer also added that the idea was to create "a really big instance. Basically a perpetual world."