[rayvio]

I've always loved adventure games ever since I first tried one on the Amiga (and I dabbled in text adventures before then even) but in the last decade or so (...suddenly I feel old!) I've also crossed over into RPGs rather more, the two genres do share a lot of elements and many RPGs have some emphasis on character interaction, inventory, 'puzzles' (granted puzzles in RPGs are almost always of the ludicrously easy variety unless they're completely optional, and even then sometimes easy) and of course story. but I can't help noticing that there's one thing that seems to crop up a lot more often in an RPG than an adventure game and I can't really think of a good explanation as to why...
replay value

I'm not just talking about a game that you want to play again because it's just that good, but about a game that you can play again and again and have it be different. thinking about it, the adventure game genre is the perfect genre for this kind of thing, yet it's the RPGs that seem to use it more

off the top of my head I can only think of a few adventure games with real replay incentive;
Bladerunner - uses a combination of random flags generated at the start of play and consequences of decisions the player makes to offer differences each playthrough
Kings Quest 6 - if I remember correctly there were two different ways to complete it, a good ending and a great ending, depending on whether you take the easy or not so-easy solution to a particular puzzle
Indiana Jones: Fate of Atlantis - has three different paths to Atlantis (Team, Wits, Fists) which all play out differently but converge on the same finale
Maniac Mansion - puzzles can be solved in different manners depending on who's in your party

and even then, only Bladerunner and KQ6 really offer different endings (Indy has a couple of 'bad' endings like letting Sophia die). granted not many RPGs have much in the way of ending variety either and those that do tend to have problems with it in sequels (Elder Scrolls for example pulled the Warp of the West out of their arses to explain the contradictory endings of Daggerfall and despite attempts at having KotOR 2 let you explain your decisions in the first game it's now been retconned as the hero of 1 being male and Jedi).

Dreamfall had a few bits that can be different, as did it's predecessor The Longest Journey, but those were just small scenes (though both games were great enough to inspire replays anyway). The Dig had a very slightly different alternative ending

if I missed any then please remind me. it may even be that there's some great adventure games out there that I've never played, just waiting for me to play them again and again