Were you there for the thread about my party getting stuck in the tomb? Because it is pretty much the quintessential example of this.
Spoiler: The One about my players being stuck in an empty tomb for three hous.
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I was running a dungeon layout I got online. It had a "false tomb" at the start to detour grave robbers, with a trap-door leading to the real tomb. There was a switch on a statue that, if pressed, causes one of the fake sarcophagi to roll back and reveal the trap-door. I made the switch real easy to find because I didn't want to waste time, but, of course, the dice crapped out on the PCs and the rogue rolled a natural 1 to search the room.
Brian, who was playing an earth-mage, then cast a speak with stone spell to ask the statue. This was, imo, a brilliant solution , and I spent a moment coming up with a personality for the statue and asked what he says to it. He then commands it open the way. I asked him to actually RP the conversation, he refused, so I told him to roll a charisma check to get the information, and gain the dice crapped out.
(Now, later, this turned out to have been a miscommunication. I thought he was refusing to talk in character and just wanted to resolve the conversation as a dice roll, which is something he has done many times in the past with the argument "I am not as charismatic as my character so I shouldn't have to think out an argument", but it was actually that he thought the spell was akin to a divination spell that forced answers from the stone rather than a spell akin to speak with animals that merely allowed him to talk to rocks. This miscommunication ate up the previous thread entirely, but was mostly orthogonal to the actual situation imo.)
At this point, the players just shut down. They had a party of 12 competent, fully rested, mid level adventurers, including a master earth-bender and a master conjurer, all completely stymied by a simple hidden door after two blown rolls. They couldn't think of anything, either magical or mundane, that could progress the adventure, and I spent three hours of real time trying to get them to try something, anything. I could think of literally dozens of ways they could have bypasses this obstacle, none them requiring specific or hidden information, but nothing. Because after two blown rolls, they had convinced themselves that I was shooting down every possible solution until they came up with some sort of "magic bullet".