function test
B777300ER:
that check is a reasonable check of system functionality, but the problem becomes a disruption to procedure following an exceptional event in the normal flow of a flight; the crew have returned to blocks for a defect, and in the clearance action for the defect, the aircraft function is unknowingly interrupted.
If the crew redo a check like the thrust level advance prior to start, then they would identify a new defect, but as they would normally do the check on the initial preflight setup, they would have to repeat the check. Humans being adept at finding work arounds and time saving behavioral patterns, tend to short circuit such activities.
On a related point:
The Reason model of causality probably fits to some extent to this event, however, the event also may serve to indicate that the behavior of aviation safety systems are in fact dynamically non linear and also have unbounded chaotic behavior, which results in stochastic or non deterministic system behavior. Accidents can happen.
About the only thing that is simply indicated is that sometimes things don't work out as desired, on spite of reasonable efforts by various parts of the system and reasonable rules and procedures.
regards