My best friend got me Mario Kart 8 Delux for Christmas a few years ago, off my list no less and I haven't gotten around to playing it. I bought Pokemon Sword the January following that Christmas and forgot about it.

First and only case. I have played every single other game I've either bought or received at least partially. Including Killer Instincts which had come with my SNES years ago and Yoshi's Island which my mom picked out neither of which had much interested me at first glance (but I had ended up loving them both).