Listen to It Only Happens Once online. It Only Happens Once is an English language song and is sung by Oscar Moore, Johnny Miller and Nat King Cole. It Only Happens Once, from the album Men in Jazz (The Greates American Men of All Time Sing the Greatest Songs of All Time - Nat King Cole, Louis Armostrong, Tony Bennett and Many Others...), was released in the year 2013. The duration of the song is 2:55. Download English songs online from JioSaavn.