An unenforceable contract is an agreement that cannot be enforced by law, even if both parties intended to create a binding arrangement. This can happen for various reasons, such as the contract lacking essential elements like consideration, mutual consent, or a lawful purpose. For example, if a contract involves illegal activities, it is unenforceable. Additionally, certain contracts must be in writing to be enforceable, as required by the Statute of Frauds. If these requirements are not met, the contract may be deemed unenforceable, leaving parties without legal recourse.