Why is the phrase Duck and Cover repeated many times throughout?

The phrase "Duck and Cover" is repeated many times to emphasize its importance as a safety measure during emergencies, particularly during the Cold War era when nuclear threats were prevalent. By reinforcing this phrase, it aimed to instill a sense of readiness and quick response among the public, especially children, in the event of an attack. The repetition serves to make the concept memorable and to ensure that people understand the immediate actions they should take for their protection.