Escape clauses that require a purchaser or an expert representing the purchaser to be satisfied with the goods or services being purchased, have been challenged as being invalid due to lack of
consideration. The argument is that a party can always escape such a contract by merely claiming to be dissatisfied. Therefore, there is no real requirement for that party to perform their obligations under the contract (to pay for the goods or services), and an agreement that only requires performance by one party is an
illusory promise, void as a contract. Instead, such an agreement constitutes a gift from the performing party to the non-performing party. Courts have generally held, however, that an escape clause containing a requirement of satisfaction nevertheless creates an enforceable contract, because a court could determine whether a claimed dissatisfaction was or was not reasonable, and therefore feigned to avoid the contract. ==International trade institutions==