Few pop earworms ever start out the way you hear them in the end, and the Chainsmokers’ “Closer†is no exception. Months ago, a leaked demo of “Closer†featuring Camila Cabello and not Halsey made the rounds on the internet, prompting many fans to envision what could’ve been. The Chainsmokers confirmed in since-deleted tweets that Cabello was their biggest hit’s original featured singer, but why Halsey replaced her remained a mystery. That is, until Cabello was confronted with the leak on Z100 today and broke the news (along with more hearts) that she ultimately had to turn down the song because she was still with Fifth Harmony at the time and they were about to put out an album. “I always tried to do my solo stuff off-cycle, so that was super on, and so I had to say no, and then that was the No. 1 song in the world,†she says. And so it goes with every famous missed opportunity. But at least Cabello can take pride that, in exchange for not appearing on one of the biggest songs of the decade, no Chainsmoker called her a “bitch†on Twitter.