The difference between life and the movies is that a script has to make sense, and life doesn't.

Mankiewicz contrasts the crafted coherence demanded by cinema with the messiness of lived experience. A screenplay must impose causality, motivation, and narrative economy—events need to “add up” for an audience—whereas real life is full of coincidence, contradiction, and unresolved threads. The remark also functions as a wry comment on the artifice of storytelling: film can feel “truer than life” precisely because it edits out randomness and supplies meaning. Implicitly, it cautions against judging life by narrative standards (neat arcs, clear lessons), while also acknowledging why stories comfort us: they make sense of what often does not.