What happens to a buildup if war never comes?

What happens when a navy builds up for war and the war does not occur?

If the buildup deters war, buying weapons that are never used can be cheaper than emergency construction after deterrence fails.

A fleet expansion that never fights can still be a strategic success. Credible capability can deter an opponent or give diplomacy time to work, even though the public never sees the battle that was avoided. The peacetime cost of ships that remain unused can therefore be lower than the lives, rushed contracts, and poor choices created by emergency rearmament. Judging procurement only by whether its weapons fire misses the preventive purpose of military readiness.