Why do Girls like the Jonas Brothers so much?

Do you like him over Zack Efron? Is it just a fad like the Backstreet boys were? What is so great about them? They sing good there obviously not ugly but its not like they will go out with fans maybe have some groupies for fun. I think they will fall out in a few years also. Thats pretty nasty that everyone knows Miley and Nick hooked upped and there under aged.