The Type 45 example separates the marginal cost of a ship from the research and industrial cost of creating its class. Britain developed facilities, trained workers, and designed systems for about twelve destroyers, then stopped after six just as repeat production should have become cheaper. Spreading the sunk development bill across fewer hulls created the misleading label of a billion-pound destroyer even though an additional unit would have cost far less to build. A twelve-ship force could have kept several hulls in reserve or refit while maintaining a larger deployable pool and could have introduced Mark 41 cells on later general-purpose variants. With only six, the Navy repeatedly worked ships hard, lacked spare crews and stores, and allowed maintenance problems to remove most of the class at once.
Notable Point · 3:28:49-3:33:21
Why stopping Type 45 production at six cost readiness
Britain paid to develop and tool a twelve-ship destroyer class, then cancelled the cheapest follow-on hulls and lost the reserve capacity needed to rotate ships through maintenance.