Every now and then, we might forget why we do the things we do. In such cases, metaphorically splashing some cold water in your face, examining the alternative, enhancing the contrast, can help.
When I was still playing Skyrim, every now and then the boredom would hit me, and then I'd kill the whole town with lightning bolts and fireballs from my hands; ending everthing that moved. Afterwards I'd survey my work and feel horribly empty inside. That feeling reminded me of what's so great about being a force for good.