The big picture !
As usual here we get bogged down in paperwork, legislation and SMS systems that are all grist to the mill of those who sit in offices and polish the seat of their trousers while producing reams of paperwork to try to avoid repetition of the incident.
The simplest safety management system starts with having the discipline to step back from a task and take time to review the work done, this can be very difficult when faced with the pressure encountered on a busy line station.
Oversight is another thing that is necessary be it self inspection as above or another person inspection the task. All of this requires common sense........ And that is something that is very hard to write into procedures. ( I know of one company that insists its maintenance staff put on protective glasses when ever they leave the crew room, this is a typical Elf & safety overkill that hampers vision for very little benefit most of the time.......... The eye protection issue should be left to the common sense of the individual when they think that the risk requires such protection)
Totally independent inspection......... That is what the "walk around" inspection by the pilots is about, this should be a broad overview and gross error check.
All of this is of course not posable without the tools to do the job be that time, company culture or external pressure, I have alluded to this in post #295.