you saw everyone put well thought and informational opinions, and you thought hey i know 3 words should be a good reply
1. raid finder gets boring after a while due to the easy difficulty. If it's your only way of raiding apart from pugs, then it will get old.
2. pvp is not balanced very well and makes the gear grind unfulfilling when you are stuck in bgs with bots. Casually finding rbg group and arena teams isn't easy at all nor convenient most of the time.
3. dailies get mind-numbingly boring after the shine wears off.
4. how many times can you level a toon before burning out? Pandaria 85-90 gets old 2nd time around fast.