Which psychological retail strategy led to the world record for the fastest product to reach one million sales globally?

The psychology behind consumer purchasing decisions has led to some remarkable world records in retail. Understanding these psychological principles has enabled companies to achieve unprecedented success in sales, customer engagement, and brand loyalty. Test your knowledge about the intersection of consumer psychology and world-record retail achievements that have shaped the industry.

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Scarcity marketing - Apple's iPhone 6S with limited edition colors (2015)
Social proof - Pokemon Go's augmented reality gamification (2016)
Price anchoring - Amazon's first Prime Day discount strategy (2015)
Emotional appeal - Coca-Cola's personalized name bottles campaign (2014)