In this case, it is the break in the movement over whether or not to try for 2010 to reverse Prop 8 or wait a whole 2 years for a more certain majority in 2012.
The 2012 folks are number crunchers. They read the polling numbers, see the trends, and also have a sense of how long it takes to create a movement capable of turning out voters at polls. They also recognize that there is a danger in trying in 2010 and losing, in that repeated loses make it harder to win in the longer term. Statistically, a win in 2012 seems almost a certainty for rolling back Prop 8 given trend numbers in public opinion and the experience in other states. (If you look at public opinion polls, it seems likely that MA would have reversed Goodridge if they could have amended their constitution in the first several months. Two years later, after everyone had gotten used to the idea, you couldn't even get a majority in the state legislature. Time works for same sex marriage movement.) But a loss in 2010 may make a win in 2012 more difficult, delaying the inevitable even longer.
The 2010 folks, as far as I can tell, seem less concerned with victory and more concerned with not tolerating second class citizenship, etc.
Maybe there are better number crunchers and strategists in the 2010 side of the debate than I see quoted in the press. But as long as this is a movement of people who care more about their feelings than about winning, it's going to keep shooting itself in the foot.