It's just a matter of knowing the secret of all TV shows; At the end of the episode, everything is always right back to normal.
— Fry, Futurama
Status quo, you know, is Latin for 'the mess we're in'.
Peter: Yeah, how did you lose your job anyway, Lois?
Lois: Ah, I don't know, Peter. Do you really care? Does anyone really care?
Peter: I guess you're right. The story's over, everything's back to normal 'til next week, so who gives a damn?
— Peter and Lois, Family Guy
Homer: Hey Mom, did you know I was blasted into space?
Mona: Yes Homer, it was national news. So... do you still work for N.A.S.A.?
Homer: No, I work at the Nuclear Power Plant.
— The Simpsons 138th Episode Spectacular
Monk: There's an old saying: don't change anything...ever.
Natalie: That's an old saying?
Monk: I've been saying it for years.
I'm the last living thing on the planet! Uh...I should have this fixed by next week, folks...
— Princess Pi, "Princess Pi vs. Everything"
Think of a shared superhero universe as something that generates inertia. At the core of the universe, very little will ever change or even bother with the illusion of change: Superman will always be Big Blue, Batman will always mourn his parents, Wolverine will always have claws and be gruff. As you get further and further away from that core, though, you get more and more freedom to do whatever you want. A good example of this is the Planet Hulk storyline, where the only given was that the Hulk would be alive at the end of it and every other character’s fate was unknown, because they were the fringe of the Marvel Universe.
Principal Skinner: If this episode has taught us anything, it's that nothing works better than the status quo.
Homer: The status quo.
Milhouse: The status quo? Ay Carumba!
Principal Skinner: That's just sad.
— The Simpsons, "Bart vs. Lisa vs. the Third Grade"