Social Scenes That End Before Their Time
The players come upon a damaged automaton amid evidence of a brutal fight.
"I need your help. I have a way to protect automatons against turning into killing machines, but I can't repair myself. Can you help repair me?"
The players look at the GM. "Nope. We're moving on. Next room."
Just like with the action scenes, much of the time if the players exit a social scene right after they enter it, the story can continue without problems.
In the example above, the automaton might have some core clues it would have happily divulged. Now the GM is faced with letting the PCs wander aimlessly with little hope of solving the mystery, sticking the clues in the next scene (where they might not make much sense), or keeping the scene going.
In this particular case, dialog with the automaton will lead into a core flashback scene you really want to run.
There are a few tricks to keeping a social scene going.
Hook Them With Partial Information
"Wait, I can tell you why the mutant bird-people are waking the ghost in the machine!" Hooks will sometimes get the players to pay attention.
Just look at this line, it lets the players know the bird-folk are up to something, and the machine coming to life has a ghost in it, whatever that means. This is bait to get them intrigued and back in dialog with the automaton.
Pretend to Forgive Them
If the players were rude or threatening to an important NPC, world-logic will probably suggest they shut the PCs out and refuse to engage. But it's your NPC, you can always come up with a reason for them to want to continue the interaction.
Say the party has just insulted a princess who is key to the story. "I suppose I need you more than you need me. Just listen for a moment, my father is not to be trusted, but he can be influenced."
The PCs can continue to discuss what's going on with the princess, plus, you can always create a price for the PCs' insolence. She could withhold resources, information, or demand they kneel and beg forgiveness when the PCs realize they really do need her help.
Second Chances
Have the NPC reappear later, perhaps this time in better shape to convince the PCs to listen.
Back to our automaton up top, the PCs could return to town and find not only has the automaton repaired itself, but it's the center of attention at a town square meeting. "And those are the people who left me there, broken and helpless. All I wanted to do was help them. They still don't know what's going on in the machine."
Feelings
If the players exited out of an emotional scene, for example one in which the King dies in the Princess's arms, you might not want to skip this because you think it sets up the tone of the next scene. But the PCs move on.
"The Princess comes to you, her fine silks soiled by her father's blood. 'It's over. I held him as he past. We spoke of many things, when I was a girl, when my first flying serpent bit the butler, and what you did. In his last moments, he told me how your forcing him out of the dream-world broke him. But he did not believe my mother would break so easily."