Charles de Gaulle airport (2004),
"There was more dust falling from the ceiling, particles of cement, more dirt. We pointed it out on several occasions," the cleaner said.
Boeing (along time ago),
Some fresh engineering grad, one of the top guys in his class, gets to Boeing for his first job. He gets told to watch a hose for 3 weeks and count the number of drops of liquid and preasure of a particular pipe connection. Eventually he complains to his manager that he's got a menial job and, after 6 years of study he'd expect something a bit more challenging. And whats the story about the leaking pipe?
"Well, if that leak fluctuates wildly, its signs that something is wrong and it could blow the building apart" - Manager
Even the most menial of workers are important.
Even if you dont understand it, the most menial of jobs can be critical.
If you're an engineer, never disregard a complaint because you think it'll never happen or because the person complaining is 'clueless' about engineering.