Over the long run, failures of function are the rule rather than the exception for biological systems, being mostly due not to malfunction but to external conditions not historically “Normal” for performance of a function. Most cognitive failures occur because outside conditions are not Normal for the particular cognitive functions attempted. When unitrackers with well-focused targets fail, the result is misperception or false belief. Failures can also occur in the operation of prior mechanisms whose jobs are to prime unitrackers, to send them after clear targets and to keep them on target as they develop. Redundant unitrackers may be maintained side by side, collecting information about the same thing by different means—so called Frege cases. Equivocal unitrackers may develop, aimed incompatibly toward two or more targets at once. False priming can result in empty unitrackers that are not aimed at anything real at all.