Motivators for poor choices are far from few. Depending on the instigator and action the motivation can be extremely different. For some it may be as materialistic as greed or jealousy. Others might have been taught that their actions are not in fact bad but rather justified for the greater good of humanity or another entity. Fear is another strong motivator for actions, due to the person believing they are protecting themselves from imminent danger or future dangers.
Macbeth from the play Macbeth by William Shakespeare is a strong example of a person falling slave to one of the many motivators. Macbeth killed multiple characters under the motivation of fear.