With specific regards to character advancement, some pen and paper systems award experience points for successful battles - battles that in a pen and paper game might take an hour or two to play through, but in a CRPG, usually take anywhere from 30 seconds to five minutes. And since many CRPGs are moving towards more freeform playing styles, where players can make a wide variety of characters to complete quests through many different means, the assumed validity of advancement systems based off of "raw killin'" becomes more and more questionable.