Eventually I just get tired of it and stop playing because I'm no longer having fun.
I realise that this is a very subjective thing but I also believe that it's not entirely outside the realm of possibility to make it have broad appeal. This is because there are tenets of entertainment that are universal and fundamental to human nature. If you've ever done film or story writing research you'll learn about how the art of story isn't as ethereal and unreachable as some would have you believe and that there are ways of making entertainment that appeals to a large variety of people who all have the one thing in common: we're all human.
This is what I feel is missing from a lot of games these days. That emotional connection that makes you WANT to be involved. Even when there's no reward from what you're doing other than the satisfaction of having done it and enjoyed the ride along the way. I truly believe that this is what made the Mass Effect series so great and also why people were so incredibly pissed off by the ending. People were emotionally INVESTED in the story and the characters. They really cared about what happened and how things played out. They loved Shepherd and the crew. People CRIED when they had to choose between Ashley or Kaiden. Hell, *I* cried and I didn't even like Ashley.
But that's the point. I didn't LIKE her. I had an emotional investment and reaction to her as a character in a story. The biggest reason why I stopped playing WoW was because I have absolutely zero interest in the story. I stopped reading quest text after about the first week in Vanilla and never started up again. The only reason I ever resubscribed was because of my emotional investment in my GUILDIES. I missed them. But that just wasn't enough to justify giving Blizzard $15 a month.
The same goes for Champions Online. I found the story just... put me to sleep. Star Trek online wasn't even really Star Trek. I had hoped so much to have some sort of connection to that world and yet it all just felt so... bland. And don't even get me started on Star Wars. RIFT was possibly the only one that got me interested but that quickly waned as well.
So... Bethesda. Make me cry.