Unlike PlayStation 3 or Xbox 360 demos, trial versions of Wii U games downloaded from Nintendo's eShop are limited to a certain number of uses.
This number depends from game to game - FIFA 13 is 10 uses, for example, while Rayman Legends is 30 uses. Sonic & Sega All-Star Racing Transformed is 15.
Eurogamer asked Nintendo why the limits on different games varied - and why there were limits at all. The platform holder replied that it was a game's publisher that decided how many times you can try their game.
"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," a Nintendo spokesperson told us.
