It is generally understood that a false statement is only a lie if the intent or expectation is that it be understood as a true statement. We have other words for different kinds of false statements: "fiction," "joke"... By saying "lie," "deception" was understood.

This is, of course, a social convention, but the application of "generally" to the subject at hand is questionable. Notice also that I was responding to someone who interpreted Alice as attempting to deceive Bob, which is not necessarily the case.