Why could interwar navies give risky destroyer officers second chances?

Why could interwar navies afford to give imperfect junior destroyer commanders a second chance?

Large fleets had enough relatively cheap destroyers to absorb mistakes while developing the aggressive, confident officers they would need in wartime, provided the navy could distinguish risk-taking from incompetence.

Destroyers were numerous enough in the interwar and world-war fleets that one accident did not threaten the whole force. Their wartime role demanded officers willing to drive toward larger opponents, accept risk, and keep a crew committed during a torpedo attack. Those same traits could produce peacetime incidents when an ambitious commander pushed the envelope. A navy wanting such aggression in war had to distinguish correctable mistakes from disqualifying incompetence. Philip Vian illustrates the value of matching people to roles: he flourished in active command while senior officers helped him avoid staff appointments that did not suit him.