What quality issue caused a 2013 recall of Lululemon pants?

A 2013 recall of Lululemon pants was caused by fabric that was too sheer, or unintentionally transparent. The problem affected certain black Luon yoga pants whose material became see-through when stretched, especially during movement or bending.

In March 2013, Lululemon pulled the affected pants from stores and acknowledged that the fabric did not meet its intended quality standard. The recall was unusually significant: the company said the affected products represented about 17 percent of its women’s pants inventory. The episode led to lost sales, customer frustration, and a highly publicized discussion about quality control.

The issue is sometimes confused with later complaints about pilling, holes, or garments falling apart. Those were separate quality concerns reported by customers, but the defining problem behind the 2013 pants recall was transparency. “Sheer fabric” is therefore the single best answer for this question, rather than a general description such as poor durability.