A( is a reward or punishment that encourages people to behave in certain ways.

I believe the answer is: Incentive

Incentive could be given in the form of financial incentive or behavioural incentive (special treatment). For example, let's say that a company provide an additional $20 per hour for those who are willing to spend their time working after 5 pm. In this situation, the additional $20 per hours is considered to be an incentive.