Post
The tendency for players in large groups to put in less individual effort, assuming others will carry the load.
Social loafing is a well-studied group-psychology effect: the larger the group, the less each person contributes. In MMO raids, 20-player content can feel less focused per-player than 10-player content because each individual matters less. Good raid design counters this with mechanics that assign specific individual roles — tank-swap assignments, interrupt rotations, or spread-out debuff mechanics — so that no one can coast.
Example
WoW's 40-man raids in vanilla suffered heavily from loafing and contributed to the shift to 25 and 10-player content. Destiny 2's 6-player raids explicitly use 'two groups of three' mechanics to force small-team accountability. Final Fantasy XIV's 24-player alliance raids deliberately segment players into groups of 8.
Why it matters
Raid designers have to fight social loafing to make cooperative content feel meaningful. Understanding the effect reveals why certain encounter designs work at scale and why 'everyone does their job' is such a load-bearing raid team virtue.
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