The German destroyer losses around Narvik damaged the Kriegsmarine's ability to expand, not simply its immediate order of battle. Prewar crews contained the officers and NCOs needed to commission later ships and train replacement personnel. A cited study of the submarine arm estimates that each early U-boat loss may have cost the equivalent of ten to fifteen submarines later in the war through lost training capacity. No equivalent destroyer study is cited, but Germany's inability to restore the arm gives the personnel argument strategic weight.
Notable Point · 3:28-5:23
Narvik cost Germany the crews needed to rebuild its destroyer arm
Germany's losses in Norway removed experienced destroyer officers, NCOs, and crews whose training value mattered more than the hull count alone.