The joke on stage

I told my dad I'd been flipping houses for a living. He said, "Good, then you can finally help me flip the pancakes, since I've been doing it alone for thirty years." Wait, that's not quite right. Let me try again with a cleaner version: My grandpa spent his whole life as a short-order cook, flipping burgers and pancakes with perfect precision. At his retirement party, everyone asked him what he'd do next. He said, "Honestly, I'm just going to lie in bed and flip the pillow over every hour until someone tells me I've been doing it wrong for forty years."