Yeah, a few years back. It was a sequel to an RP ('d run before, and as the kind of GM I was, I gave my players relative creative freedom, since this one was more open worlded than the one before it. Well, I kinda lost track of what everyone all was doing, my main overarching plot started unraveling/getting interfered with by various player plots, and at some point I just stopped really caring. It was helped by one particular person joining who forced sense back into it, and some attempt to get that overarching plot back on track, but disagreement over it in the player base, and previous damage, meant that it was just a matter of time. 

But I don't feel bad about it. I'll get around to another segment once I have a good idea.