"The Bystander Effect" experiment

Below is one experiment that I have seen for a long time represents the bystander effect. 

Guys, you may not like this :'(

https://www.youtube.com/watch?v=dtVHnZX8E50&oref=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DdtVHnZX8E50&has_verified=1