Kacey and Harry teamed up for the love song in June 2018 while Harry was performing at the Madison Square Garden and their performance quickly went viral afterwards. Even hearing the moment from a crowd member's phone doesn't dull the quality of the performance, but instead leaves people yearning for more. Thus, the reason the duo was made the winner by social media.

Congratulations to Kacey and Harry on their big win!

https://www.eonline.com/news/1023348/kacey-musgraves-is-a-green-goddess-on-the-2019-iheart-music-awards-red-carpet