Problems which when taken to the mechanic mysteriously disappear, only to reappear as soon as the mechanic is out of sight.

Probably related to the inverse phenomenon, DemoMeltdown.

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Also called ''veterinarian's disease''. There is a physiological basis: scared animals pump adrenaline that masks subtle symptoms.

Advice to programmers: stop scaring your programs...

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Also related to the ProgrammerProximityDetector