lomapaseo, you are quite right to ask “… what is there left to fix? … to prevent the next accident.”
However, one safety defense, the take-off config warning might have been disabled by maintenance action. Thus in addition to the “ 1:10-4 error ” by the crew (possibly a multiple as it could be assumed that each crew member individually suffered at least one error), there could be a similar multiple from maintenance error.
This might only illustrate the nature of accidents as being combinations of rare circumstances; where the absence of any one could have prevented it. Problems occur if the circumstances become commonplace – complacency, bad practice, poor checking/checklists, management oversight, etc.
If the circumstances are really rare, then the probability of an accident becomes extremely rare (not necessarily acceptable). Thus, the defenses should seek to minimize the occurrence of ‘individual’ error circumstances, thus further reducing the chance combination. Whilst crew and maintenance CRM, TEM, and airmanship can help, so too can the organizational safety climate and safety culture, none of which we have details of.
Inf:
“Revisiting safety and human factors paradigms to meet the safety challenges of ultra complex and safe systems.”