Why do some people always have to seek ways to destroy one another?

I’m sure in life, we all have made mistakes that we would like to change but can’t, however why do some individuals make it their mission to throw it back in someone’s attention, when things don’t go their way. I feel things of that nature cause people to fall in destructive patterns that they are unable to reverse due to their own conditioning. My life experiences concerning the above mentioned has made me understand that in all reality that age and maturity do not align with some individuals.