How did Greek rhythm differ from the strong-and-weak beat patterns used in much modern Western music?

Ancient Greek rhythm differed fundamentally from the strong-and-weak beat patterns characteristic of much modern Western music because it was quantitative rather than accentual.12

While modern Western music typically relies on meter—the organization of beats into regular groupings where specific beats are emphasized through stress—the Greek rhythmic system was derived from poetry and based on the duration of syllables. In this quantitative system, rhythm was determined by the relationship between long and short syllables, which were defined by the time required for their pronunciation, rather than by a recurring pattern of accented and unaccented beats.1342

Because the Greek system did not rely on the periodic stress or "strong-and-weak" accentual metre found in later Western traditions, it functioned as a durational substructure that prioritized the length of sounds over the dynamic emphasis of a pulse.125