If a contract is said to lack consideration due to uncertain performance this can mean three different things in business law. Although all three ideas are distinct, each results in an unenforceable contract. The consideration requirement can be met if one of the parties to the contract forfeits their right to purchase their widgets or sell their gizmos to another company. However, illusory promises may result if one of the parties reserves the right to exchange the widgets or gizmos with another company not involved in the contract. If this reservation of rights is present in a contract, the contract becomes unenforceable because it would lack consideration.