Why Nintendo still doesn't have a trophy/achievement system to their games in 2015?

[Ostro]

I love how some people (again) just post that the Wii U would sell tons more just because of something they do like.
Achievement/Trophy hunters are a mere minority among gamers and while it is pretty prominent and "in your face" on the Xbox (PS is a little more discreet) it's still just 0.x% of gamers who actually care what's popping up every now and then (based on players on major leaderboards vs console sales). If that's (+0.x%) what the Wii U needs in sales to be successful and you believe it can be developed with magic and no working time, then yeah, Nintendo needs it.
People who do not own a Wii U definitely don't understand what's going on with the stamps and Miiverse integration in games. They may only learn now that MS is trying to do similar things bringing more social stuff with their monthly updates.