The Tales of Tyria Guild Wars 2 Podcast closed up shop last week with an interesting and insightful comment on the state of MMO's - the idea that games can't just be fun in the abstract, but need to be fun when you are playing them to win.
Bridger and company aspired to world-competitive levels in GW2's world versus world non-instanced PVP combat. They found that the most effective strategy in this format is to form up into the largest concentrated force possible, to ensure that you can quickly kill off your foes, capture your objectives, and move on to the next point. Defensive measures that might otherwise have served as force multipliers to help smaller groups hold off the masses through sound strategy - such as siege engines - were inadequate.
Bridger's comment was that any game can be fun when you're messing around with your friends - a past example involved splitting his entire guild into five-man groups just to see how many different "orange swords" conflict icons they could light up on the minimap simultaneously. To be worth playing competitively, however, the game has to be fun when playing to win. Sheer force of numbers as a dominant strategy simply wasn't fun.
I can't speak to the merits of Bridger's claims, having never even played Guild Wars 2 (that I continued to listen to his podcast after deciding not to bother picking up the game is pretty much my highest endorsement). That said, I find it compelling because it fits with what we see across the genre.
In many cases, there's absolutely nothing wrong with the design of gear grinds, daily quest grinds, random group (PVE or PVP) grinds, and all the other things that modern MMO's use to attempt to drive player engagement. Some are buggy, some are excessive, and but many are technically well implemented and most are fun in some form if you are running them with your friends - that would be why they're your friends. Where MMO's may be falling down is in the experience of a player who is playing the game to win - to contribute as much as they can to their raid group or just to beat a personal best time to collect their daily rewards.
I often write that incentives have been highly successful in changing player behavior and highly ineffective in changing player preferences. As Bridger notes, the underlying game itself has to be fun or burnout will be inevitable.