The panel argues that German submarine expansion was constrained by trained people as well as hull production. An early U-boat loss removed officers and specialists who would have formed the experienced core of several later crews. The cited estimate treats each submarine lost in 1940 as preventing roughly fifteen later boats from being effectively generated through that training chain. Better Allied anti-submarine performance at the beginning of the war could therefore produce effects far beyond the immediate tonnage sunk.
Notable Point · 3:09:18-3:10:19
Why early U-boat losses had a compounding personnel cost
Destroying an early German submarine also removed experienced sailors who might otherwise train and lead many later crews.