The secret of Apple's success in selling premium tech as an affordable luxury

Apple's hardware designs, software, icons, marketing, retail strategy, and branding have all been closely copied by its rivals. One thing they aren't copying is Apple's vast, premium installed base of loyal buyers. That's the primary foundation of Apple's wildly successful, global business that's uniquely selling massive volumes of luxury-class, premium-priced products in markets where competitors fight over sales of low-priced commodity units with thin margins. Why can't anyone else achieve what Apple has?