But clearly they knew they had something special on their hands. Enter Danish singer M�, who ultimately co-wrote and sang the finished track. The end result: Spotify's most streamed-song ever (as of November), according to Billboard.

And surely, M� appreciated the opportunity to sing the song more than the aforementioned superstars would have, as it raised her profile considerably. "I'm so thankful and so happy for that song and for Diplo and Major Lazer for trusting me and taking me with them on that adventure," she told Radio.com earlier this year. "It was not forced, like: 'Oh, this has to be a big hit; this has to be like this and this and this.' We just made a song and thought it was cool and nice. And it makes me really happy to see that you can actually make a big pop hit without it having to follow all these classic rules. That song just, from my end and also from their end, I imagine, just came out of pure love for music."