I finally understand why I clicked with Diablo so profoundly as a child struggling with ADHD: the action-RPG was literally designed to remove as many barriers as possible between the player and "clubbing a skeleton."
In an interview originally conducted by Edge magazine, now republished in Playmakers: The Inside Stories of 30 Iconic Video Games, Condor (later renamed Blizzard North) co-founder Max Schaefer shared some of the earliest design philosophies that informed the conception of Diablo. According to Schaefer, the creators felt RPGs at the time were too complicated, took to long to get to the good stuff, and focused on penalizing players more than rewarding them, resulting in dwindling audiences.