You are Not So Smart Blog: The Celebration of Self-Delusion
Originally published March 25, 2011 (and still relevant)
The Misconception: You make rational decisions based on the future value of objects, investments and experiences.
The Truth: Your decisions are tainted by the emotional investments you accumulate, and the more you invest in something the harder it becomes to abandon it.
The blog post is here.
Note: This heuristic may be one reason psychologists hang onto patients longer than required.