Compare that to the 2013-14 period, when its losses jumped threefold on the back of revenue growth of about €260 million. A big reason for Spotify's unprofitability is because it pays out a great deal of revenue to the music industry. Most of the millions it earns in revenue flows out as royalties to record labels. Of the €1.9 billion it earned last year, €1.6 billion was spent on royalty payments. Why is Spotify's wage bill growing so substantially? In its note to investors in its latest filing, it offers an explaination: "We depend on key personnel to develop great products and services, as well as operate our business, and if we are unable to retain, attract and integrate qualified personnel, our ability to successfully grow our business could be harmed," the board writes. "If we cannot maintain Spotify's culture as we grow, we could lose the innovation, teamwork and focus that contribute crucially to our business."