What are double coincidence of wants?

Double coincidence of wants is when two people both want exactly what the other has, like a perfect match!

Imagine you and your friend are playing in the park. You have a red ball, and your friend has a blue bike. You really want the blue bike, and your friend really wants the red ball. That’s a double coincidence of wants, you both want what the other has!

But now imagine another kid has a green scooter and doesn’t care about balls or bikes. If that kid wants your red ball, but you don't want the green scooter, then it's not a match for you. That’s when things get tricky.

Sometimes, people have what they want, but they don’t have what others want. Like if you have a red ball and want a blue bike, but your friend has a green scooter and wants a yellow hat, that’s not helpful for either of you.

That’s why having matches is like finding the perfect trading partner, everyone gets what they really want!