"In England, in both wars, we manufactured very large quantities of wooden aircraft, which always seemed to be having joint troubles of one kind or another.
As far as aircraft are concerned this was not wholly surprising, for I remember being shown, right inside vital glued joints in the main structure:
1. A pair of scissors
2. A first-aid manual (pocket size)
3. No glue at all
On the whole I do not think that most of these accidents were caused by sub-normal or abnormal people; I am afraid the guilt lies with very ordinary people, and that was just the trouble. Naturally, people get tired or bored, but I think the root of the matter was much deeper than that. Very few of those who made, or failed to make, these joints had any personal experience of a situation in which the failure of a joint could cause a fatal accident, though collectively they had a great deal of experience with things like cupboards and garden sheds, where the strength of the joints mattered very little. All our efforts to persuade them that a badly made joint was morally equivalent to manslaughter foundered on a deeply held folk tradition that it was silly to fuss about such things and that strength is a boring subject anyway. All this would not have mattered so much if it had not been practically impossible to inspect the joints properly after they had been made."
Seriously, I think even though times have changed we can't rely on policies and on other people doing what they are told. We are all ordinary people and a policy can't expect to stop people getting bored or tired, some people might say policies increase levels of boredom!