INFINITE's song "She's Back" was originally one of SHINee's songs

 Fellow K-pop group INFINITE's 'She's Back' composer finally been revealed. The original composer of the song had gave it to SM Entertainment. And SM had chosen SHINee to sing the song. 

It was originally supposed to be on their album "Lucifer" but they had a quick conference and decided that "She's Back" didn't mach the concept of their album. They felt like the song had a had a boyish feel to it (different from the Lucifer album, which had a darker feel to it). Therefore they decided to leave it out of the album. 

So, Then SM gave the song to INFINITE. The composer was quite disappointed that the song could not be apart of SHINee's album but said that INFINITE did a great job making the song lively and thanked them.