What happened

Shares of Ollie's Bargain Outlet Holdings (NASDAQ:OLLI) are trading down nearly 10% on Monday after the company announced the sudden passing of CEO Mark Butler. The discount chain was already under pressure from investors after missing on earnings earlier this year, and the company's challenges will be all the more difficult to manage without the guidance of its longtime leader.

So what

Butler, 61, passed away unexpectedly on Sunday after spending Thanksgiving with his family. He had served as CEO since 2003 and was a key architect of Ollie's growth in recent years. Board member Richard Zannino said in a statement that Butler will be hard to replace.

A shopper goes down the aisle of a retail store.

Image source: Getty Images.

Zannino continued:

Mark was an exceptional entrepreneur, merchant, leader, philanthropist, friend and family man. From ringing the first sale in the first Ollie's store in Mechanicsburg, PA, in 1982, to leading the company's highly profitable growth to 345 stores in 25 states, Mark built a successful and enduring retail concept, assembled an incredible team, created thousands of jobs and delivered millions of bargains to our customers, while delivering exceptional shareholder value along the way.

Shares of Ollie's had climbed more than 300% from the company's 2015 IPO through early 2019.

The board named John Swygert, who is currently executive vice president and chief operating officer, as interim CEO.

Now what

Swygert, who has been with Ollie's for 15 years and served as chief financial officer for more than a decade, takes over at a challenging time. The company's shares were down more than 30% over the past six months even before Butler's passing, pressured by same-store sales that fell 1.7% in the fiscal second quarter and earnings that fell well below expectations and led to a lowering of full-year guidance.

Butler built a strong foundation, and the company seems unlikely to collapse without him. But his death is sure to lead to fresh uncertainty about whether Ollie's Bargain Outlet can manage its rapid growth and doubts about whether the company can regain its title as a top growth stock.