The word 来不及 is formed through a logical sequence of concepts: it begins with the idea of an action or event "coming" (来), then introduces a negation (不) to block that coming, and finally adds the concept of "reaching in time" (及). This creates an intuitive cause-and-effect chain, the intended action cannot commence because there is not enough time to reach the point of execution, thus conveying the unified meaning of "it's too late to do something". It is a compact narrative of a failed attempt due to time constraints.