According to the PBS documentary on Bing Crosby, his famous duet of "Little Drummer Boy" with David Bowie (
Little Drummer Boy) almost never came off. They were scheduled to sing it on a Crosby Christmas special, but Bowie refused because he said he hated the song and was only doing the special because his mother liked Crosby. A couple of musicians working the show got together and in an hour wrote the bridge accompaniment "Peace on Earth" for Bowie to sing along. This appeased him enough that he ended up doing the bit and it became a classic.....