"You can be the bad thing that happens to somebody". Have you ever been the bad thing in someone else's life?

I know this video is surrounding Gun Laws, but forget that. Please, pay attention to the words of the inmates, because that's what I want to focus on. They are aware of the bad they have done, the consequences of their actions. We can think of other things besides killing someone with a gun: bullying, shaming someone, insulting someone, whatever it is... have you ever been the bad in someone else's life or just day? Were you ever the person that made someone else's day just shitty? If yes, do you regret it? Or did you wanted to do exactly that? ---- Let's see how it goes, Carla. Wishing for the best.