God I totally f***ing hate multiplayer... It's fun for a short while but then it becomes this time/life consuming bad habit.
No more real pleasure in playing, you just play the same repetitive MP because you can, for the sake of killing time, when you could be enjoying a new engrossing story in another single-player video game.
There's also another reason I hate multiplayer (the PvP kind anyway): it brings out the jerks and can make us a lot more aggressive, put us in a bad mood and ruin our day.
Finally, f*** those guys who turn their first single player campaigns into speed runs and those in industry who use them as examples in deciding whether to continue pursuing the single player game mode.
People make us angry. If we lose to a computer we get pissed, but we all know there's really no one to be angry with there and no one else knows about it, our "honor" is spared. When we lose to a human opponent online we get mad, because we imagine him laughing at us (because that's what we do when we win). Plus, people cheat, camp, glitch, insult each other and do all sorts of things to annoy other players. Small wonder online gaming is such an angry environment.
Unfortunately the new generation of gamers seems to like nothing but that: when they're not playing online shooters they're playing MMOs, and even for single player games they prefer Borderlands, Dark Souls and Pokemon with their uncomplicated assembly line dynamics and no real story to pay attention to.