Contract Breach

Not a separate wrong. The name comes from systems that treat a contract as a binding promise, and under title transfer nothing is left for it to name. Where a Contract has moved title and the holder keeps the thing back, that is Theft, and the new owner is the victim. Where the condition for transfer has not happened, no title has moved, so the holder took nothing and no one has a claim. Where the parties set a penalty on failure, that penalty is itself a conditional transfer, and it passes on its own terms. A party who cannot deliver has taken nothing; only a party who can deliver and refuses becomes a thief. Renegotiation is not breach either, because it needs consent from all parties.