The idea of "complacency" is just another desperate try from the human performance buffs to say something meaningful about "human factors".
It is an almost completely meaningless term when it comes to trying to unserstand how humans and machines interact. It is just another way of saying "human error". It makes a "neat" and "holistic" case for studying folk models of how accidents occur. "Complacency" is equally non-specific as the Yerkes-Dodson "U-curve".
Automation does not just solve problems. Like any other innovation/solution it creates new problems as well. If you cannot trust in automation - why use it? Using the word "complacency" in an accident investigation is just judgemental and over simplistic. One often hears that "the crews trust in automation was UNJUSTIFIED". So far, I have never seen anyone try to explain why the assumption of satisfactory system state was regarded as JUSTIFIED by the crew. If their trust in autiomation were unjustified, and the crew knew that, they would not make the assumption and would consequently not become "complacent".
IŽll write more later, after the staunch folk model worshippers have had their say!
