In both Cataclysm and Mists of Pandaria, Blizzard made the terrible mistake of second guessing their playerbase. Before, in each expansion, Blizzard gave handouts to both the casuals and the hardcores, however you wish to define them, by massaging game systems and coming up with unique ways to handle the different ways that players can play. I want to take you on a sort of informal journey through time and space and look at how Blizzard addressed the needs of everyone.
Vanilla WoW - Huge Time Commitment
In vanilla WoW, there was little that you could do that would take less than a lifetime to achieve. Raids were 4 to 5 night a week things that you had to do, that only 40 to 120 players on each server really ever got anything done. There were usually one main major raid guild (of 40 players), and then one to two guilds that could also progression raid. The time commitment was literally the requirement of sitting in your chair for eight hours 3 nights a week being a lifeless husk trying your hardest to contribute to these insanely epic encounters. Outside of that, dungeons required the cordination of finding other players, traveling to the dungeon, summoning the group, working out everyone's roles, and then hoping that no one disconnects the entire dungeon.
It was hell. Oh, attunements.
Anyone remember attunements? You know the quest of doing 2390423 things in 2342342 dungeons and hoping that it all somehow gets you access before your guild advances to the point you can no longer join 'em? Yeah.
The Burning Crusade - Serenity Starts
In TBC, Blizzard got a bit more aggressive about time and removed 40 man raids, because that just really made it impossible for anyone to do anything. They instead created a tiered system, dungeons like Karazhan were for PUGs and small guilds while the raids and attunements were for larger parties and more serious gear. This gave everyone something to do. TBC was like al dente pasta, it had a lot of bite to its content, but you could do any of the dungeons in less than half an hour. With the introduction of heroic dungeons, or dungeons specifically for level 70, players were able to get enough gear to do dailies (another TBC invention) to complete side-quests for neat loot.
Wrath of the Lich King - The Golden Years
In WotLK Blizzard said screw it and just literally made two paths, sort of like in high school, one path was for players without much time (10 man raids and heroic dungeons) and the other path was for players with a ton of time (25-man raiding). For the most part, it worked really good. Blizzard kept iterating on the concept throughout the expansion and it ended with everyone happy. Ulduar was playable by almost everyone in the game, and everyone got gear and it was just cool and amazing and awesome.
Cataclysm - Serenity Ends
Blizzard started to say ya know what, WotLK was too easy. Players by the end were literally dragging the entire dungeon with them start to finish and AoEing everything down. So let's just nerf EVERYTHING into the ground, make tanking and healing incrediably unfun, and deny everyone gear at the start and make everyone suffer while they play through this horribly sombering storyline about death, destruction, and the end times. Let's culminate it with a dungeon in which you kill Deathwing over a year because there isn't anything better to do, while stripping out all of the fun mechanics like talents and adding in reforging to make the game even more complicated for little benefit.
Mists of Pandaria - Clown School
Well, Blizzards knee jerk reaction was to just undertune everything and make dungeons into clown shows and the entire game into a circus. With the newly implemented raid finder, there was nothing much to do, and with everything retuned out of "SUFFER" mode, the game just sort of felt like any other MMO out there. It lacked anything distinctive, beyond a bland storyline about mystical forces and some arsehole orc named Garrosh. The bright colors, cartoon pandas, and simplified talent system plus easy mode everything made everyone sort of just say why bother.
Warlords of Draenor - WHUUUUUT?
So, somehow, Blizzard in their genius came to the conclusion. Hardcore players do not like to do PvE and will min/max their way out of it, so let's not focus on making that part of it difficult and remove it as much as possible from the hardcore component. Then, make the PvE engaging and fun enough that players who like to just take their time can find a lot of enjoyment in it, then make sure that all characters are OP in PvE as much as possible, allowing them to get through it at their own pace. Then, readjust raids so that guilds can field as many people as they want to gear and allow the optional use of the new gear system to help players gear up even faster. Then, to top all of it off, make all of these systems fun and engaging.
Oh and add in what's pretty much a Farmville like component so even if the game is running in the background, you're still good to go.
So big round of applause to Blizzard. Let's see if we can keep this perception going for a patch or two. Are you going to take a card?