When the contributions of individual group members are identified, so that everyone (or at least the leader)knows who did what, social loafing is greatly increased.

Social Loafing

The tendency of individuals to exert less effort on a task when working in a group compared to when working alone.

Contributions

Acts or offerings that aid in advancing a cause or improving a situation, often involving time, money, or effort towards a collective goal.

Identified

Something or someone that has been recognized and named as being a particular person or thing.