an economy goes along based on one person producing what another wants (more or less)
and money represents the relative value between producer and buyer,
what happens when the buyers return it without having paid for it, yet no-one else wants it?
what happens when the buyers don’t pay at all, or claim it has no value, or claim they can’t pay even though they have consumed it?
what happens when the producer gives up because no-one wants/can afford/wants to pay for what he produces?
what happens when this is on a huge scale?