A combination of things really. I made myself a list of pros and cons and made my descision to quit from there.
Pros;
- Graphics. Despite being somewhat outdated, I really like the graphics in WoW. Add to that the fact that there haven't been any sudden Suspension of Disbelief-breaking graphical changes and instead gradually improving quality, makes this a big plus in my book.
- Warlock class quest. I found this to be so awesome it deserved a point in the pro-catagory. Even if it's just in the hope of future class quests like this.
- Transmog brings a lot of vanity customizability. I really like this.
- The game doesn't punish players severely if they don't have 40 hours a week to play. Which I don't. Not by a looooong shot It might take a bit longer to get to where you want, but you can get there regardless of the amount of time available to you.
- Brawlers guild. A great and fun addition to the game.
Cons;
- Subscription-based game. Kinda grew out of this when you have excellent games such as GW2 and TSW which are Buy to Play with a great in-game store that doesn't provide P2W items. I can spend my money on the game when I want to and keep it in my pocket if I need to.
- Pandaland and Cataclysm. Qua lore and setting, I found both to be extremely uninteresting. Cataclysm because Deathwing was a complete joke throughout the expansion. The old world revamp was needed but it was turned into a far too linear leveling experience. Pandaria because I find the whole westernized Asiatic setting to be appalling.
- PvP and PvE balancing has never worked, doesn't work and will never work. Period. They need to be seperated, full stop.
- Dailies everywhere. And while dailies on their own are not a problem as long as they are not mandatory, at the start of the expansion you were pretty much forced to grind 'm for the valor gear. Luckily, Blizz seems to recognize this problem when I look at the Timeless Isle stuff and the fact that they are no longer mandatory to progress your toons.
- Pandas. Yes, this is my personal opinion, but I find Pandas completely out of place as a playable race. They should've remained a small and mysterious race that pops up now and again instead of dominating an entire expansion with their faux-chinese accents, alcohol addictions, architectural rip-offs and a poor excuse to twist and shoehorn the zodiac system into the game.
- Little love for 5-man content.
- LFR. While I find the idea of everyone being able to see the PvE content admirable, it's tuned to be way way WAY too easy. And before you start bashing, I'm not talking about rewards here. I don't care if other people get easy purples. It's purely the fact that half the raid can go AFK in a voidzone and you can still complete LFR easily.
- Talent system. It has little variety even though they wanted to create just that with the new system. There are still cookie-cutter builds for every class and talents are often a very obvious choice to make (with a few exceptions). I'm not expecting TSW-style systems where you can litterally unlock 150+ talents/skills and build your own personalized build (which is awesome btw), but the current talent system in WoW has no depth whatsoever.
- Lifeless combat system compared to the newer MMORPGs out there. Combat is mostly based around boss/mob mechanics rather than the actual class abilities. It should be a more even 50/50 split between the two.
- The in-game community. Beyond the guild there barely is any server community anymore. Unless you count random racist remarks (which I report), yelling, screaming and various 'ANAL' variations as a lively community. Everything is group finder, nothing is communicated anymore.
So, yeah... The con-catagory pretty much had this one in the bag for me.
Note that this all just my personal opinion. No need to bash this post if you disagree.