I don’t know if I’d say all consequences need to be disclosed ahead of time. I think that in most cases, a sense of the risk inherent in an action that’s to be attempted and some sense of the odds, too.
For example, in my 5E game, I almost always share the DCs for any kind of action roll. Keeping those unknown just leaves the door open for fudging and illusionism or even just the possibility of those things. And for what? To obscure the chance of success?
If there was in-fiction evidence the PCs could use (e.g. quickly examining the wall they're about to climb) then I'd have no problem with telling them the DC at least in somewhat specific terms, but non-numeric as the PCs wouldn't be thinking in terms of numbers and I generally try my best to narrate things as seen/known by the PCs.
If there's no in-fiction evidence to go by (e.g. they're trying to sneak across ground they've had no way of pre-scouting and thus they've no idea what the ground is like or what might be met there) then they ain't gettin' no DC nohow.
And in situations where even the premise of what they're trying is open to question, i.e they might be trying something they don't realize is impossible, not only do they not get a DC but I do the rolling behind the screen for them. The most common of these is trying to disbelieve an illusion. If they end up still believing it I don't want them knowing whether it's due to a bad roll or to there being no illusion present at all.
I think you have to honor the dice results. If a player achieves a success, a GM adjusting things so that the success does not stand is undermining player agency.
There doesn’t seem to be any other reason for it than a GM deciding “no, that’s not how I wanted things to go...I’ll just go ahead and change that.”
I think
@prabe has hinted downthread at a corollary question here: while success should clearly be honoured in the moment, for how long does that success remain valid?
Using my example of the Baroness from upthread a bit: the PCs talk to her in order to determine if she knows anything about some missing jewels, and on a few successes conclude that she legitimately and truthfully does not. The PCs take this success and turn their investigations elsewhere.
However, the PCs in asking her about said jewels have, as a probably-unintentional side effect, just informed her that the jewels are in fact (according to them, anyway) missing. In your view does it invalidate the PCs' successes in that conversation if the Baroness then acts on this new-to-her information behind the scenes in a manner that may or may not affect the PCs down the road, depending how things go?
I don’t personally follow that mentality. I have no problem allowing PCs to fail. However, the mindset for the fail forward approach you’re critiquing here is that there are times when failure will bring the game to a halt, and so therefore, fail forward is about finding alternative ways to apply consequences than simply declaring a failure and then watch as everyone stares at each other for a half hour.
The intention is to keep the game moving in instances where it may otherwise slow or stop. And I know that you personally don’t mind when a game slows to a crawl, but there are plenty of us who do.
To me, if plan A has stalled out it's on the players/PCs to come up with a plan B and try that; and if no plan B suggests itself then abandoning whatever it was they were trying is also always an option.
I'm reminded of a PC in one of my games who, when first brought in to the party in a recently-abandoned Dwarven city, was a rescued prisoner and badly hurt. They didn't have the resources to patch him (and all the other rescuees) up, and he was in no fit shape for adventuring, so they plopped him in front of an old vault door with the other rescuees while they went out to rescue some more.
This PC was a thief. A greedy one. And, as I soon found out, a stubborn one.
And they'd put him in front of the vault door of a Dwarven bank.
So instead of sitting there recovering, he tried moving heaven and earth to get into that damn vault! Neither the PC nor the player knew (though both kinda suspected) his chance of successfully stealing anything was less than zero; but it was: not only was the PC the wrong race (the door would
only open to a Dwarf; the PC was Human) but if he had managed to open it he'd have been dead - or worse - the moment he tried to enter as he didn't know any of the passwords to disarm the various lethal glyphs and curses.
This is a classic case where 'just give it up!' comes into play...but some players (and some PCs) just can't wrap around this concept.
And this is not even addressing that a success with complication isn’t really a failure. You succeed at what you attempt, it just doesn't go perfectly.
I agree with this statement as long as it's applied when 'success' is rolled and not when 'failure' is rolled.
I don’t know if this will help, but maybe don’t think of the game as trying to simulate criminals committing crimes and instead think of the game as trying to simulate a crime story. Because if you read some crime fiction or watch crime movies, things begin in media res all the time. Relevant details and plans are revealed in flashback....all the time. The criminals have the items they wind up needing....all the time.
All that stuff is baked into crime fiction.
Which is fine for someone who's reading a book; but for someone trying to play a character in a game setting, having things happen non-sequentially kinda butchers any idea of one thing or action or decision leading to the next.