I think it's more about the personality types of drummers. Have you ever met a drummer? They're...another type of person. 

drummer are out of their god damn minds. i think Animal from the Muppets is the most realistic interpretation of a drummer I've ever seen. you MUST have swagger to be a drummer. there's just no such thing as a staid drummer, a respectful drummer. if you've got insane rhythm and like to beat shit up, you are Relevant

Travis barker, Tommy Lee, Questlove. Why is the drummer the it person in a band? Sometimes more than the lead. What is it about beating those sticks on that material that makes drumming so … relevant 

Why are the drummers always more important than the lead singers

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