Ok, guess fisking is the proper way to respond to this.
The GM can choose to kill characters at any time, for any reason. Is this expected? The GM can choose to tell players that every single thing they try to have their characters do fails, and describe humiliating results. Is this expected? Frankly, stepping a bit outside the rules, the GM can be a complete monster and verbally abuse the players with no provocation. Is this expected? If the test of expected is that it might happen, then congratulations, you've just made discussion of anything about the game pointless, because so much is now expected.
So, just to be clear here. You are equating changing a single die roll result to auto killing a PC? To automatically failing every single check that a player could make? I just want to be absolutely clear that this is the comparison you are making.
It's not needed at all, and, frankly, most of the rough edges aren't player facing because they exist in adventure and encounter design. Just check the boards for the perennial topics and you'll see this.
End result of what? The only things I had in the post is the GM fudges or the GM doesn't and the latter doesn't do the same as the former. I'm assuming you're reaching back to reroll mechanics, here? That's been thoroughly contested and you haven't yet addressed those counter points, you just keep saying the thing contested. To sum up:
You're committing the inform logical fallacy of a false equivalence. You note that since reroll changes the rolled value and that a fudge also changes the rolled value that these are therefore the same thing. This ignores quite a lot. Firstly, when you reroll, you replace the 1st rolled value with the 2nd rolled value. Both are fairly rolled, both have the same chances to succeed or fail. With fudging, there is no fairly rolled replacement -- the GM determines the outcome that they want, then, if necessary, arbitrarily selects a value and pretends that it was rolled. The method is different.
Nope. This is false. There are numerous reroll mechanics where the better of two results are chosen. There are also numerous mechanics that simply change the target number needed - Shield being the clearest example of this. So, no, you do not always replace the first roll with the second.
Secondly, a reroll exists within the ruleset.
Just like fudging.
The rules tell you when to apply the reroll and how to apply the reroll.
Just like fudging - although, to be fair, the when and how are largely left up to the DM.
Fudging is discarding the rules in favor of the GM's whim (you can call it judgement, if you'd prefer, but it's still arbitrary). This is the difference between following the rules of the game and breaking the rules of the game. Even if you lean on the discussions across editions on fudging (which is entirely missing in 5e except for the one blurb that talks about how hiding dice rolls allows the breaking of the rules, nothing on when, how, or why to fudge) it is explicitly presented as the GM using their position and secret rolling techniques to break the rules of the game in pursuit of some other goal. This is also often recommended within these same discussions to keep the fudging secret, so the breaking of the rules should be done secretly -- the exact opposite of a reroll.
No, the same thing is not done. You're moving to the conclusion and assuming that the end solely justifies the means. That a reroll cannot force the same end while fudging always does is a third point to consider -- one is a chance to change the first rolled outcome, the latter is a guarantee to do so.
Except when there are numerous mechanics that change the first rolled outcome flat out. Which you seem to be continuously ignoring for some reason that I cannot quite understand.
But, yes, I do agree that I'm moving to the conclusion. I'm not sure where you are getting the notion of "justification" from though. It's not about justifying anything. I don't have to justify anything. It's right there in the rules. As far as I'm concerned, there just isn't really any difference. In both cases, the results are altered after the fact. And, realistically, the player side mechanics are far, far more used than DM fudging. I seriously doubt that any DM fudged every single encounter. But, there will be reroll style mechanics used every single encounter. Making it player facing simply made it a LOT more common in the game.
And, that's fine because the player side mechanics are generally quite fun. So, great. It's a better idea. Moving fudging from behind to the DM's screen to the player's hands has certainly resulted in a better game, IMO. I'll not argue that it's worse.
