Why more interwar ASDIC money alone was not enough

What if Britain had devoted more resources to ASDIC in the late 1920s and 1930s?

Major gains would require building and operating many more escorts, because wartime-scale use drove the decisive learning.

The Royal Navy was already investing heavily in ASDIC during the 1920s and 1930s. The great wartime gains came when many ships used the equipment under operational conditions and produced a large body of feedback. Reaching that learning rate before the war would require a near-wartime program of sloops and escorts, not merely a larger research grant. Sensor development thus depended on fleet scale, doctrine, and repeated use.