Definition - What does Illusory Promise mean?
An illusory promise is a contractual promise that cannot be enforced because it is too vague.
Illusory promises are often the subject of breach of contract suits. In such cases, if a promise is found to be illusory, then the promising party will not be held liable for damages because the promise was too vague to be upheld.
Justipedia explains Illusory Promise
Illusory promises are different from enforceable promises in which one party makes a clearly defined promise to another party in a contract.
An example of an illusory promise would be if a waffle company promises to deliver "a whole bunch of waffles" to another party by December 1. In this case, it is not clear how many waffles constitute "a whole bunch." Thus, the promise would be considered illusory, and it would not be enforceable in court.