I think this one is interesting because it marks one of the rare instances in which The Beatles turned to the blues for inspiration. They were rather unique, among a sea tide of blues based bands, for not being in the least bit a blues based band. The Beatles were unrepentant pop lovers, who leaned on the rockabilly of Elvis and on the far less cool basis of pre-rock popular music. They didn’t care very much about pretensions of authenticity and somewhat looked down on those of their rivals who had them. I’m sure that element of purity helped them maintain their undeniable toppermost position in the rock pecking order for as long as they were a unit.