I don't mind grinds either, in fact that's one element of Diablo 2, probably my favorite game of all time that kept me playing it for so long. That and an interesting PvP scene for me, those 2 are all a game needs to be amazing imo if they're done well.
The adventure to 80 was awesome, and the game is still among the most visually stunning MMO's I've ever seen.
The problem was what were we grinding for? The loot wasn't hugely interesting as there weren't random modifiers or tons of gear to grind/farm for, and eventually everyone just ended up with the same stats. So while I don't mind gear grinding, they didn't make it worth the time. As for the PvP scene they made it hugely annoying, sPvP was extraordinarily luck based and no good team match set-up or even player run tournaments and events gave me no interest to play there either. No amount of fancy graphics or random themed events will keep all of its players interested if they don't give them something to do in the end. They wanted to take some of the "negative" aspects of MMO's out in that gear differential could be amazingly imbalanced for PvP where the casual cannot compete with the hardcore. But it just ended up with no real differences between characters, not to mention most class + wep combinations suck and there's only a handful worth using. They tried too hard to get so many different things covered that a lot of the core mechanics suffered for it, hence why I don't play anymore.