Starbucks’ move to bring back Howard Schultz for a third stint at the helm could prove treacherous for investors, based on the track record of so-called boomerang CEOs.

The coffee chain said Wednesday that Schultz will return as interim chief executive officer next month with Kevin Johnson retiring. Schultz was the architect of the coffee chain’s expansion in the ’80s and ’90s before stepping down as CEO in 2000. He returned to the role eight years later and led the company until Johnson took over in 2017.

Schultz, 68, is among a fraternity of boomerang CEOs that includes famed corporate leaders such as Steve Jobs, Michael Dell and A.G. Lafley. In general, stock performance under repeat CEOs is about 10% worse than those taking the reins for the first time, according to research from the University of North Carolina’s Kenan-Flagler Business School.

“I see Schultz going back to the basics, and that might not work now,” Kenan-Flagler professor Christopher Bingham said. “To get someone coming back for a second time, that’s a rare event, and it makes me especially worried.”

Bingham and colleagues analyzed the performance of 167 boomerang CEOs at companies listed on the S&P 1500 index from 1992 to 2017 and compared their tenures with those of more than 6,000 other chiefs over the same period. Founders, who accounted for almost half of the repeat CEOs, “often lack the administrative skills necessary to manage the challenges associated with a larger, more complex organization,” especially one that is in crisis or requires a turnaround, the academics wrote in an article in MIT Sloan Management Review in September 2020.

While Schultz didn’t create Starbucks from scratch, he’s credited with transforming it from a local java roaster into a global phenomenon. The company now faces rising costs, geopolitical uncertainty in China and a growing unionization movement across the U.S., not to mention lower foot traffic in urban areas due to the popularity of remote work.

To be sure, Schultz’s first return to the reins was good for investors. The stock rose more than 500% during his tenure from 2008 to 2017, compared with a 67% gain in the S&P 500 index.