News that Spotify has formed a partnership with Vodafone in Ireland is fairly routine. Such partnerships are commonplace, and Spotify has partners throughout Europe. But one news report contained a bit of information that shows the value of a mobile partnership to money-losing startup: the partnership is being supported by a $2 million marketing campaign.
To put that in perspective, a $2 million advertising budget in Ireland is the equivalent, on a per-capita basis, to a $137 million advertising campaign in the United States. Ireland has about 4.6 million people. The U.S. population is around 314 million.
A U.S. carrier wouldn't necessarily spend $137 million on a marketing campaign with a partner. But the size of the Vodafone market campaign helps explain why Deezer has waited to enter the United States. The market for its product was immature and it's a large, expensive place to launch a product. Although the U.S. market has great potential because of its size, a music service would be financially prudent for delaying a launch until a partnership could be acquired. 
Subscription services, spending to grow and faced with slim margins, need all the marketing help they can get. Consider Spotify's financials. Last year, Spotify's net loss increased to $77 million from $59 million even as its revenue grew 128% to $573 million from $247 million. After deducting cost of sales of 83.5%, Spotify had 16.5% of revenue, or $95 million, to spend on necessities such as salaries, rent, equipment and marketing.
Scarcity will increase the value of a U.S. mobile partner's marketing budget. Subscription services outnumber major mobile carriers. Beats Music is reportedly seeking a mobile partner for its U.S. launch. Deezer appears to be securing a mobile partner here, too. That leaves two major mobile carriers for the remaining services. In this numbers game, somebody is going to lose.