Watch the The V Chord Example online guitar lesson by Jeff Scheetz from Blues Jam Survival Guide

Lots of times there will be a solo going on over these four measures when we start on the 5 - it is used as an intro to the blues. When you hear a guitarist start out with a solo lick and then the band kicks in, sometimes that is a "starting on the 5" kind of deal. Listen for it next time you are checking out your favorite blues player and see if you can catch what chord they are starting on.