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Drives and desires can be described as a deficiency or need that activates behavior that is aimed at a goal or an incentive. These are thought to originate within the individual and may not require external stimuli to encourage the behavior. Basic drives could be whereas more subtle drives might be the desire for praise and approval, which motivates a person to behave in a manner pleasing to others.

By contrast, the role of extrinsic rewards and stimuli can be seen in the example of training animals by giving them treats when they perform a trick correctly. The treat motivates the animals to perform the trick consistently, even later when the treat is removed from the process.