Why didnt 38 witnesses do anything to try to help Kitty Genovese when they saw her being murdered?

In short, the answer can be summed up as "diffusion of responsibility", which in social psychological terms, translates to the number of persons in the group, dictates how fast a response to emergencies will be given. In other Words, the more people to a group, the less likely it is for any individual group member to act "individually" and seek out help. This is so because it is hypothesized that an individual will think to themselves "someone else will call for help", which if all 38 people are thinking this, then who is calling for help? There is also the shock & awe value of a traumatic situation, meaning a shocking event more often than not, can cause delay in a group setting. Think of a fight in a public setting, more often than not, individuals of the "group" gather around first to see whats going on before any type of preventative action is taken to stop the fight. I wish I could remember the exact terminology for these phenomena, but these are the general ideas of those terms. Maybe someone else can fill in any blanks that I may have missed.