Barry didn’t write “I Write The Songs” either, one of the more execrable ditties of the 70’s.
Problem with big fame and fortune is the entertainers sometimes start to believe their own BS. The Beatles were so huge and the hype so pervasive they could literally put anything on an album and it would sell. It’s got to the point the record companies mine the archives for outtakes, and the enthusiasts argue whether it’s Ringo or George belching on take 20 of You Know My Name (Look Up The Number).
[hijack] It was written by Bruce Johnston of the Beach Boys. The first recording of it I heard was by Captain & Tennile, who were members of the Beach Boys’ touring band and had come to be friends with Johnston.
Or maybe not a hijack since Campbell also had toured with the Beach Boys briefly.