FROG: *puts cookies in box* There. Now we will not eat any more cookies.
TOAD: But we can open the box.
FROG: That is true.
What was that willpower thing you mentioned again, Frog?
Seriously, though, it does an amazing job of introducing a relatable character dilemma, showing the struggle, and resolving it (for a certain value of resolving, anyway) in a way which is very concise but also clear and puts you right in the moment with them. It probably helps that we've all been there, whether it's with cookies or some other food or activity which will have negative effects if we over-indulge, but still. I feel like I should be taking notes on writing technique.