It was a surprise. The fact that we were able to detect it I think was an important piece of detective work. It was literally the needle in the haystack, or more accurately a different-sized straw in a haystack. It is something we now know about, and now I think inspection methods and things will be appropriate to that. But at the time, it was an unanticipated problem.
On November 4th, 2010. See this statement in context.