Another thought, consider the effect of Cognitive Dissonance.
A fella saves up for an entire year for the truck of his dreams. He finally gets it, but it constantly breaks down. It turns in to a huge money-pit. Does he admit to family, friends, or himself that he made a huge mistake? Or does he pretend that this lemon is what he really wanted all along?
http://www.flickr.com/photos/justinandelise/523412023/in/set-72157600291449109/
The fiercest defenders, sometimes, are those who deep down fear they just made a huge mistake. It's much easier to "go with the flow" than to face that embarrassing detail.