You know when you make the perfect toasted tomato-and-cheese sandwich? With a tasty, juicy tomato in thick slices, and some sharp old cheddar, and coarsely-ground black pepper. With the stone-ground whole wheat bread toasted to the exact perfect crispiness, and the layers of tomato and cheese perfectly constructed. When nobody interrupts your progress, so by the time you slice the sandwich in two and sit down to take the first bite, everything is still fresh and warm.
And then, with that first bite, the top layer of toast scrapes the top of your mouth raw, so that every chewing motion hurts, and the pleasure of savouring your perfect sandwich is lost.
I hate that.