Here's a comprehensive summary of the Wikipedia article on designer clothing:
Designer clothing represents high-quality, luxury apparel bearing a renowned designer's label, originally crafted by a specific individual but now widely encompassing designs licensed by a brand or person. This practice of licensing, pioneered by Pierre Cardin in the 1960s, became a common industry standard by the 1970s. While identified by famous brands, the actual designer may not be the founder—for example, Virginie Viard designs for Chanel today—and the quality can vary based on licensing agreements; these items, especially designer jeans, typically cost hundreds of dollars. The premium denim market experienced a significant shift after the Great Recession, with experts like You Nguyen of Levi Strauss noting an end to "$600 for no reason" jeans, as only about 1% of the 450 million pairs sold in the U.S. in 2018 cost over $50. This higher price point stems from superior fabric, unique hardware, intricate washes, and special distressing techniques, with U.S.-made jeans often exceeding $200 due to stringent labor and environmental standards.