Originally Posted by
DaDaDan
The captain is given the ultimate decision to accept or reject the plane because it is his responsibility to safely operate the flight. Unless his rejection is particularly unwarranted or is clearly made with ulterior motives, second-guessing him for exercising his authority in a grey area will discourage pilots from exercising their authority and decrease safety of flight.
Basically, if you tell the captain he can reject the plane, but he'll be second-guessed and/or punished for doing so...he doesn't really have the option to reject the plane anymore.
Most pilots are professionals at what they do, flying airplanes. They are
not professionals at maintaining airplanes. You are not "second guessing" them by telling them what the maintenance manual says.