When Yoox and Net-a-Porter merged last year, they created what Net-a-Porter’s founder, Natalie Massenet, described as the “world’s biggest luxury fashion store.” There’s a big balancing act inherent in that title. Luxury goods rely on scarcity, high prices, and prestige. How do you reconcile those demands with an huge online operation selling designer labels that are often on sale? That’s Amazon’s big problem as it tries to lure designer labels onto its site. As successful as it has been in becoming the “Everything Store,” it has yet to crack the high-end fashion market. It could take some lessons from Yoox Net-a-Porter. Read more at Quartz.