I once heard someone say, accept that no one is perfect. The secret to finding your soul mate is to find someone whose flaws don't bug you.
It's kind of like that with Destiny. Some people couldn't get over the lack of story. Some couldn't get through the repetitive mission designs. For some the grind was too steep.
For me, all those flaws are there, yet it's the most fun I've had playing a game, since....well, I don't think I have a since.
Beyond that I'm really fascinated with the passion Bungie is pouring into the detail of the game. The way the UI team keeps refining menus, the way the sound effect for collecting a bounty has been updated. Twice. They're working like mad to build out content, but they're also really sweating the small stuff along the way. I've never seen a game evolve like this before. It's not only getting larger over time, it's getting dramatically more polished. I'm really interested to see where the Taken King goes with this. I have a feeling it's not going to be a stand alone thing - some buckets of content - but more like a full reboot of the game.