When Jack Vance was writing 'The Dying Earth' he probably didn't realize the spell memorization concept that he developed would influence role-playing for decades to come. Gary Gygax decided to adopt the system for his fledgling wargaming system and the rest is, as they say, history. Fragile, grey bearded wizards who painstakingly memorized spells and waited for opportune moments to unleash magical mayhem became a staple of the role-playing genre.
Fast forward in time and a change begins to take place. The RPG genre begins to migrate from the tabletop to computer. But translating the RPG from a slow paced game that can be played a couple of times a week, when all your players can fit in the hours required, to a game that can be played every night by a single player on a computer that crunches the numbers at lightning speed, well, that results in problems. The PnP systems of old weren't designed for this new environment, they were designed for smaller doses of content dished out less often. So computer RPG designers pad the experience, adding in vastly more combat encounters than any PnP game would have.
