After ‘What You’re Doing,’ my favorite song on Beatles For Sale is John Lennon’s ‘I’m a Loser.’ Lennon dressed up his famously low self esteem in a song about a failed relationship but really about his own insecurities.
Lennon was paying a lot of attention to Bob Dylan at the time, and this is the first of his songs that makes that influence clear (it would become more clear with ‘You’ve Got to Hide Your Love Away’ on the band’s next album).

