Characteristics of people

I sometimes think why people can be so mean at times. Why they are picking on someone's others lives. Why hurting people that doesn't do wrong with you. We only got one chance in this life, one life to understand what the world we choose to live and how could we become who we are. So, why wasting time on picking up someone or hurting someone. We should be more focus on what would our life to be. How will we get there. That's what I thought rn.