Honestly, they don't really even need good stories, if I have guildie friends, like in Ragnarok (which also doesn't have good graphics/anim, so it was really jsut a grinding game for me). ArcheAge was a bit boring for me because the story is so-so, while I didn't have anyone to run around with.
Okay, so, yes, Ragnarok DOES have quests and such, but I almost never ran quests given the rate of leveling on pservers.
I suppose Ragnarok's an exception. Nowadays, I just want stuff to do besides the usual fighting mobs. I want to gather stuff on TERA and craft things. That habit carried over to ArcheAge.
On Mabinogi, I used to always only fight and run dungeons, but then Stray told me that I really should try to up my stamina (I was running out of stam halfway through battles because I'd only focused on combat, which...uses a lot of stam), so I started working on "life skills". In Mabi, those include...like...cooking, gathering eggs, milking, gathering herbs, potionmaking, etc. And that got so fun and was a really nice break from the usual fighting, that I've spent the past several rebirths (ever rebirth is about 3-4 weeks, when I'm actually active) just farming away at herbs, haha.