This event offers a case in which measuring the performance of one service or
agency may amount to nothing more than sub-optimization. The reason is that
measuring the performance of one subsystem (i.e. the bird sanctuary) yielded no useful
information for assuring an acceptable performance across the board. In other words, it
could not prevent the failure of another subsystem (i.e. aviation) and thus the
performance of the system as a whole. After all, the performance of a system is equal to
the performance of its weakest component (Seddon, 1998).