At long range, a fake turret or funnel can change a ship's apparent identity. An aircraft crew that dismisses the contact at that distance may leave without taking a closer look. The disguise only has to sustain that mistake for a few minutes to give the ship an advantage. For a raider already moving at full speed, the delay can buy time to get away from pursuers.
Notable Point · 4:18-5:18
How a distant misidentification could buy Graf Spee time
A distant aircraft that dismissed the disguised ship could give a raider at full speed a few minutes to get farther from its pursuers.