Finishing British battleships followed the logic of retaining proven capabilities while new weapons matured. Aircraft might sink an enemy capital ship, but a navy could be more certain that its own battleship offered a direct answer. Commercial procurement can tolerate failure that ends in bankruptcy, whereas a mistaken wartime fleet decision can kill personnel, lose a war, or threaten the state itself. Navies therefore tend to keep the established system in production until the replacement can demonstrably perform every necessary role.
Notable Point · 1:05:36-1:07:19
Why navies retain proven capabilities
Fleet procurement keeps proven systems alongside promising replacements because failure can cost a war rather than merely a balance sheet.