After waiting years for a true follow up to Diablo II, fans couldn't quite grasp just how much Blizzard fumbled the launch of Diablo III.
The new story campaign the devs added seemed to go against the grind that the series had always been about, with the endgame content not living up to what fans expected from a title that they were supposed to constantly come back to.
Thankfully, the introduction of an Adventure Mode remedied this, letting players loose to explore as much as they wanted without having to follow the constraints of the main narrative.
Likewise, another major point of contention when the title first dropped was its market. Instead of focusing on straight trading between players, each person in a server was encouraged to sell their high-level gear for real money. It meant that richer players could just buy the loot they needed for extortionate prices, a system which was decried by the majority of the fanbase and eventually removed entirely.
These were only the main changes too; pretty much everything in Diablo III was overhauled in the years following its release, transforming a good-if-underwhelming RPG into one of the most addictive and compelling games of the decade so far.