Javascript setInterval clearInterval Simple Example Not Working Explained?

Question

I have a very simple JS setInterval and clearInterval example that doesn\'t work. There has got to be an underlying reason why it does not work and I would like to know why

Answer 1

change

var automessage = setInterval(function(){ something() }, 2000);

to

automessage = setInterval(function(){ something() }, 2000);

in turnON()