Super Mario Run’s revenue projections have been dashed by almost 75%

Maybe people aren't a fan of the $10 price tag?

Super Mario Run may have the biggest launch in the App Store's history, but that apparently has not translated into sales for the highly anticipated runner. The game was downloaded 2.85 million times on launch day and carried an initial financial forecast of $70 million in its first month. That forecast has been massively reduced by almost 75% according to SuperData to between $12-15 million. 

SuperData said:

"Based on the early numbers we see coming in and the response from consumers, we expect Super Mario Run to initially earn on the lower end of our forecast, around $12-15M in its first month.
Requiring to 'always be online' is prohibitive and the game is still a bit too heavy-handed for quick-play on a phone."
The "always online" feature has always proven to be a controversial decision, no matter what kind of game is being talked about. Not every wireless customer has a plan that includes unlimited data, and even some home providers (such as Comcast) lay down data caps as well. 
The other thing to consider is that with the mobile platform, you are dealing with a much broader range of customers, many of whom are non-gamers. These non-gamers are used to their apps being free to download with some optional microtransactions sprinkled in. Super Mario Run, on the other hand, is a few free levels and then a pay wall if you want to play the rest, which for these people, is against their norm.
$10 is also a lot for most apps when looking around at the competition. That's not to say that Nintendo isn't right to ask for the $10, it's just a matter of dealing with the buying tendencies of a new target audience. If these projections hold, we could very well see a price drop and/or microtransactions added to the game to make it more "accessible" for mobile players.
Source: [PowerUpGaming UK]