An interesting difference in table top rpgs* and story games** is their accessibility. To be clear I don’t think either style is more accessible, but each one is accessible and inaccessible in different ways.
An advocate of story games will extol the virtues of simple mechanics, saying complex rules, charts and tables get in the way of coming up with an interesting story. They are not entirely wrong in saying this but I will go into more detail about that later.***
I have seen players accustom to rpgs try to play a story game, it can be very awkward when someone is asked to frame a scene and they are not ready for it. These same players can participate in a normal rpg but find story games quite difficult to play. In many ways the advancement of story games has been about easing the difficulty of scene framing.
I judge rpgs and story games based on their ability to inspire my play. I call this an “I want to” moment. If you have made the player want something inside of a context then everything else to falls into place. It’s easy to start a scene if you know what you want and where you are.
An rpg creates the “I want to” moment usually during character creation or selection. Why do 9 out of 10 players have streetwise as a skill? Because streetwise is an evocative word that has both a want (to be wise) and a context (the streets). The rpg has even more tools for creating “I want to” moments. a fantastic piece of character artwork depicting something like strength, wealth, or attractiveness can make a player think “i want that”. Artwork can even create context if the character’s looks say something about the setting. Some rpgs use interesting game mechanics to create “I want to” moments. A player may build a character a particular way because they want to make 6 attacks with a blaster rifle each round. This want is sometimes called power gaming, while I see the reason most people don’t like this trait I will explain later how it can be used for good and not evil. *x4
A story game will typically address “I want to” issue head on, some literally have players write a goal on their character sheet. This is a neat way to focus a player but this is not a way to inspire a player. Setting a goal is the result of inspiration. Story games work well with people who are easily inspired, it may only take them 20-40 pages to get a story game rolling, it could take an rpg player 100-1000 pages.
How players frame a scene, each item, action and motivation in a scene is a result of everything the game has inspired up to that point. Just like a play that features a gun in the first act, if a game includes rules for gunfire, or a picture of a gun, you can be sure someone will eventually fire that gun.
*Rpg is here defined as D20, Savage worlds, and Cortex
** Story game is defined as Ocean, Prime Time Adventures, and Fiasco. Games like burning wheel and Apocalypse world are more like hybrids (they also rock and are my favorites)
*** Few rpgs have what I would describe as complex rules, they are simply presented in an unfit format (hint: it’s books), so it’s true, the games are hard to learn and do get in the way of storytelling, but I blame the book, not the rules.
*x4 power gamers are responding to systematic incentives, this kind of play is encouraged and rewarded in EVERY sort of game aside from rpgs and British war gaming clubs. These two cultures are similar because they play games that are incredibly unbalanced systematically and instead chose to balance these games with soft social methods. Systematic game play is great and perfectly viable method to create “I want to” moments if the game is balanced to the tastes of the audience.