Should a navy buy more small destroyers or fewer powerful ones?

Is it better to maintain many small, replaceable destroyers, or build a few ships as powerful as possible?

Neither rule works universally: a navy needs enough hulls for its missions, but each must still be strong enough to survive its likely opponents and perform cruiser-like duties when required.

Henderson's warning and the battles of Narvik undermine a simple quantity-versus-quality formula. Smaller H-class destroyers performed well when surprise and numbers favored them, but were badly punished once stronger German ships could respond. The later arrival of Tribal-class destroyers illustrates the value of a heavier fighting element. Global presence and occasional cruiser duties can also force destroyer size upward. The useful question is whether the force combines adequate numbers with ships strong enough for the missions they will actually receive.