In a interview with POP CRUSH BTS have said:
You Never Walk Alone is a side story or supplementary story to our previous album Wings, and we wanted to tell a different story that was not told in Wings. That is one of reasons why the BTS members look somewhat different, perhaps a little bit more casual and younger, in the YNWA artwork. The same idea goes for the “Spring Day" video. The song is based on memories with old friends who we don’t see anymore and we wanted to visualize the story in the video blended with additional metaphors.