The article hints at the pattern, but I think it&#x27;s worth mentioning directly: it&#x27;s fairly common for a psychologist with a pet theory to publish a self-help book based on it. This creates an incentive to exaggerate the scope, size, and certainty of the effect they claim to have discovered, because their status as a scientific expert on the phenomenon becomes a marketing tool. Even if they don&#x27;t engage in any deliberate misconduct, this could still create bias that leaks into study design and analysis&#x2F;interpretation.