AsianFin -- Lululemon Athletica lowered its annual profit and sales forecasts for the second straight quarter on Thursday, warning that weakness in its U.S. business, product missteps, and higher tariff costs are weighing on results.

Shares of the Vancouver-based yogawear maker plunged about 15% in after-hours trading following the announcement.

The company, once credited with pioneering the athleisure boom, has been struggling to regain its footing amid intensifying competition and shifting consumer preferences. Weekly product launches, intended to boost momentum, have failed to generate a meaningful sales lift as Lululemon heads into the critical holiday season.

“Once the trailblazer in athleisure, Lululemon has lost its innovation edge, now squeezed by luxury newcomers like Alo Yoga and private-label dupes with comparable fabric tech at lower prices,” said Suzy Davidkhanian, analyst at eMarketer. “Copycat culture highlights how far the moat has shrunk.”

Lululemon has also struggled with merchandise management, leaning too heavily on underperforming categories such as lounge and social wear and missing opportunities to capitalize on seasonal trends. Those missteps have alienated some U.S. shoppers, its largest customer base.