It’s not something we haven’t seen before—play limits on demo games—and it’s been showing up on Wii U demos just as it has on the 3DS. If you’re not familiar with this (then obviously you haven’t been playing any demos), it means you can only play a demo a certain number of times before it no longer becomes available to access for further use.
The folks over at Eurogamer.net asked Nintendo “what’s up with that?”, and particularly why the play limits vary with each title we see. A Nintendo rep had this to say about it:
“Each publisher has the opportunity to decide how long demos will stay on the eShop, and how many times consumers can play them before they expire.”
For example, once the demo limit is over and you try to use it, you’ll see a prompt that asks if you’d like to see the full game in the eShop—which you have the option to them purchase, providing it’s still there. So, if you don’t like them? Blame the publishers, not Nintendo!