I'm thinking here of an Indian place near my office that graduated from ghost kitchen to food hall restaurant. I had their food both before and after, and the difference was night and day. I actually didn't want to try the food hall version, based on my experience with their ghost kitchen incarnation. But a friend convinced me to give them another chance, and now they're one of my favorite places for when I want to splurge on lunch.
I don't really know what the difference is, but I'm guessing it's that they didn't get to have a kitchen setup that was well adapted to their menu at the ghost kitchen.