Suppose you have a task X that must be performed on a large scale - that is, everywhere within the jurisdiction of some large unit - but of such a nature that it is best performed by smaller units.
The performance itself is best left to the smaller units, but it is up to their parent units to - shall we say - manage the task and ensure that it is getting done reliably and, under many circumstances, consistent with how task X is being performed in other units.
The larger units are best suited to coordinating the tasks of the smaller units, and not for performing a task which is most efficiently served by the smaller units.
It is of course possible for some larger task Y to come along such that the smallest efficient unit size is larger than those needed for task X, but the argument could then simply be repeated with new definitions for smaller and larger units. |
