Another way for an offer to terminate is by death or incapacity: The death or incapacity to contract of either the offeror or offeree prior to acceptance terminates the offer. See Restatement (Second) Contracts ยง 48.
The Restatement notes that recent cases and statutes have created some exceptions in the case of the death or incapacity of the offeror.
We note this rule for the sake of completeness, but do not discuss it further. It is more important to focus on another way in which offers terminate: lapse of time.