Okay, imagine you and your friend want to play together but you haven't decided what game to play. Your mom comes and says you have to clean up your room before you can play. So you both agree to clean up your rooms and then play the game you both want. But what if your friend changes their mind after cleaning their room? Or what if you can't agree on what game to play? This is kind of what an incomplete contract is - it's a situation where you agree to something, but there's still some things you didn't agree on. In business or law, this can happen when two parties make an agreement but there are still some details left out that they need to figure out later. So, it's kind of like a puzzle where you have some of the pieces but not all of them. And you have to work together to figure out how to finish the puzzle.