We're pretty bad, as a species, at predicting our own future behavior.
When gas prices go up, we say we'll drive less. But we don't. We say we're going to vote in the upcoming election. Many of us won't. And some of us even threaten to pack up your belongings and leave the country if your candidate of choice gets beat by the undeserving bum he's running against. Yeah, not likely.
And. turns out, we don't always tell pollsters the truth. Freakonomics co-author Stephen J. Dubner puts it this way: "All political polls rely on one stranger telling the truth to another stranger about the future, so there're a lot of ways that could go wrong."
"The cardinal rule," says Dubner about soliciting our true opinions, "should be this: don't listen to what I say, watch what I do."