"Ain't No Sunshine" was inspired by the film Days of Wine and Roses, with Bill Withers reflecting on how people can sometimes miss things that weren't good for them, much like the film's characters. The song captures a feeling of longing and absence. Notably, the repeated "I know" section was originally intended for more lyrics, but Withers was advised by other musicians to leave it as is. This track, from his 1971 debut album Just As I Am, marked a significant breakthrough for Withers. Playing this song channels a deep, melancholic yearning for someone who has left.