Why is a packet that is received after its scheduled playout time considered lost?

A packet received after its scheduled playout time is considered lost because it can no longer contribute to the real-time data stream, such as audio or video, without disrupting the continuity and quality of the media. In real-time applications, timely delivery is crucial; late packets can lead to delays, gaps, or out-of-sync playback. Consequently, these late packets are effectively discarded, as their intended purpose has passed, and they cannot be integrated into the ongoing stream.