Development
Very young children begin with an external locus of control. As they develop a conscience and a set of core values, then they can learn to guide themselves with an internal locus of control. Certain types of childrearing practices contribute to an external locus (e.g., overemphasizing rewards) while others help to nurture an internal locus (e.g., reasoning). Rewards can be effective in moderation. If they are overused, a child can begin to focus on the reward and not behavior. So if the reward is not there, then children may not do what we want them to do.
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