The story is tight. Perhaps not unique, but they don't waste time with side plots or scenes that don't serve the main story. It's tight, focused, and fast. The song matches the mood; while you might not love the tune, the pacing and theme is in perfect sync with one another. The animation is self-aware. While these aren't mind-blowing graphics, it understands its own limitations and stays within its lines.
Ultimately, the point is that the video stays focused on the story it's telling, it doesn't waste time with extraneous plots or gimmicks, and it keeps moving forward. It's easy to see why Here Without You gets so much praise.
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