Why Japan persisted with shipboard anti-aircraft rockets

Why did the Imperial Japanese Navy make anti-aircraft rocket launchers work when Britain did not?

Japan persisted and had more peacetime development, while Britain could abandon the concept for an effective 40 mm gun.

The difference was not that Japan discovered an effortless solution. The Imperial Japanese Navy kept working on the rocket concept because it wanted that form of defence and retained more time before entering the war. Britain had a more attractive alternative in a capable 40 mm anti-aircraft gun. Once a conventional weapon could do the job, the incentive to rescue an unreliable rocket system fell sharply.