Usually, when one singer (invariably singing for one character) ends up singing two versions of the same song, it’s because the story has changed circumstances for the character. It could be—in most cases—that happy days have given way to sad; or ennui has made room for a sense of purpose. In some (relatively rare) cases, the same singer sings two different versions of the same song for two different characters.
No, this song list isn’t the result of a dear relative landing up in jail or anything of the sort. It just popped into my head one day when I was looking up a song on Youtube and saw Lapak-jhapak in the side panel. It occurred to me: Hindi cinema has its fair share of people who are in prison, at times in really dire straits (not the case with Lapak-jhapak, where David’s character is really quite comfortable), but still being able to summon up the energy to sing. As a character writes in Alice Walker’s The Color Purple, Why do tired people sing?… Too tired to do anything else. Maybe that’s the case with film characters in prison: lots of time on their hands and too depressed to do anything else.