American Eagle Outfitters was founded in 1977 and became a popular American lifestyle clothing brand targeting young adults and teenagers. The brand's flannel shirts became wardrobe staples in the 1990s and 2000s, representing casual American style and comfort. Flannel shirts appeal to a wide demographic seeking affordable, versatile casual wear that works across seasons. American Eagle's accessible price point and quality construction made their flannels popular for everyday wear, maintaining steady demand in the secondhand market.