It's like the bully that's careful to not get caught for years.

Then one day a victim snaps and punches the bully in the face, so the bully beats the shit out of their victim and since "he started it" they get equal punishments. For the bully it's part of the game, for the victim it makes them feel crazy and possibly teaches them to never stand up for themselves again. Or drives them to do something incredibly dangerous because they feel trapped.