An unenforceable contract is an agreement that cannot be enforced by law, even if both parties intended to create a binding contract. This can happen for various reasons, such as the contract lacking a necessary element, like consideration, or if it involves illegal activities. For example, if two parties agree to a contract for an illegal service, such as selling drugs, that contract is unenforceable. Similarly, if a contract is not in writing when required by law, it may also be deemed unenforceable. In such cases, neither party can seek legal remedies for breach of contract.