It appears that explicitly rewarding children for sharing leads them later on to

Question

Quizplus · Accepted Answer

Studies have shown that explicitly rewarding children for sharing can actually result in them sharing less often in the future. This is because they begin to see sharing as a transaction rather than an act of generosity, and they only share when they know they will receive a reward. Once the reward is no longer offered, they may stop sharing altogether.

It Appears That Explicitly Rewarding Children for Sharing Leads Them