On some rare occasions, he didn't.
- P.S. I love you has Andy White on drums (Ringo on Tambourine)
- Love Me Do: some versions have Andy, others Ringo
- Back in the U.S.S.R and Dear Prudence have Paul on drums (Ringo had temporarily left the band)
- The Ballad of John & Yoko was Paul - Ringo was playing in a movie at that time (it is rumoured John was so grateful for Paul stepping in, that he decided to release "Give Peace a Chance" with Lennon/McCartney credits
- Eleanor Rigby (no Beatles played any instruments on this one)
oh, and there is one more song that Ringo doesn't play drums to: BECAUSE, since it does not have percussion at all :)