Why not? The old expression is if at first you don't succeed, try , try, again.
In a game with open ended rolls, it should be possible to gauge a success or failure by the value of the percentile roll. Roll low enough, and you jam the lock; roll high enough and you don't even scratch it.
What do you mean by "then they can't open it," though? It sounds like the stake in what you're proposing is essentially time — the number of retries you can be bothered with; keep at it and you'll eventually make the check? — or was that supposed to imply that the lock will, say, jam after a few tries, F1/F2-style?
I mean they cannot open it (now); and if it has a penalty that drops their skill to... (well some games would be zero, but I think in a fallout game it should be 5%), then they cannot open it until they improve (or get really lucky in Fallout's case).
* When I was six years old, I was out by the pool in our apartment building; I reached up over my head and spun the dial on a combination lock to the pool supply closet ~ then I pulled on it, and it opened. That was a fluke chance. I locked it again, and never succeeded in opening it a second time. This can happen, but it's not likely to.
In RPGs it's useful to have the probability of something be a guideline rather than an absolute rule; in a PnP game, the DM or GM can allow a novice to (for instance) manage to pick open a lock ~because it could happen, and if it serves the story, they can make it happen. Fallout 2 doesn't fail you on the first lock in the Temple of Trials; (or at least, I've never seen this happen). But having a strict rule that dictates success or failure at your current level, imparts the expectation that you can do it again (perhaps when you shouldn't be able to do it so reliably).
I don't think the speech example is really applicable. That character would be written without a speech check in his dialogue tree.
No... that would be awful... it robs the PC of the chance to succeed due to consummate skill and or a bit of luck. In that example it should just be very difficult, but not impossible ~perhaps so difficult that most players don't realize that it
is possible. IMO it should only be impossible if that's exactly how the designers want it.
Realism aside, I think it's valid to question the gameplay value in random failure.
Just as I think it's valid to question the gameplay value of assured success. I generally lose respect for any RPG that follows that route.
Does it make the game better/more fun? Does it aid or work against role-play?
IMO it facilitates roleplay, and I did not find Fallout's use of thresholds to be fun... less so for the fact that it was a radical change to the established skill system.
If we play with the idea of a % check for speech F3-style, I really think this works against. Why randomly prevent me from going the Speech route here that I've built my character for?
Because they are not perfect, and the alternative means that they are; even a professional with decades of experience can make a mistake, or have unexpected misfortune. It may be a very slim chance, but it's not impossible ~and shouldn't be IMO.
I really think this just promotes save/load'ing, and while that's up to each player, I find it hard to promote a mechanic with this consequence as successful.
It does, but they would reload for anything that didn't go their way ~that's an ego trip where you back up to rewrite history (in the game) to force everything to go their way. Would you think the same same of a casino where you never lose because the player might reload until they win?
(http://www.youtube.com/watch?v=SC05Pb7Qd68.
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