Quy tắc chấm điểm bóng chuyền hiện đại: Rally points, set đấu và set thứ năm đến 15 điểm

core: Volleyball uses rally scoring with best-of-five sets first to three wins, and the fifth set is played to 15 points with a two-point margin. Deuce occurs in 8-9% of sets, with average set score around 25-17. This format makes rotation discipline and serve consistency critical.
key_facts: Rally scoring adopted at 2000 Sydney Olympics, making every contact consequential.; Deuce frequency: 8-9% of all sets; average set score: 25-17.; Best-of-five median sets: 4, with 3-1 as most common outcome.; Fifth set: 15 points, two-point margin, no ceiling, increasing variance.; Libero: free back-row substitution but no serve, block, or attack restrictions above net height.
source: Volleyballmag.com rules explainer with KeepTheScore dataset (~700 matches); context around 2024
related: Q: How does the fifth set to 15 points affect strategy? A: It compresses variance and rewards momentum swings in deciding sets.; Q: What is the rotation fault rule? A: Positional disorder at serve hands opponent a point and the serve.; Q: Why is serve consistency now more important? A: Every rally produces a point, so a weak server costs immediately.