>>53147833People have reasons for all the actions they do, implicit or explicit. They are not always obvious, but you can reflect on the action and understand/analyze what prompted it. It is not always easy, especially if it is some childhood trauma that prompted the taint of the character and persona, though, sometimes you may need professional external help.
I assume it feels good to overpower smaller weaker creature and make it submit, but that is a surface reasoning.
