Data storage company Western Digital Corp. gave shareholders the jitters today after announcing plans to replace Chief Executive Officer Steve Milligan (pictured), who will retire next year.

Milligan, who has led the company since 2013, said in a conference call that he intends to stay on for the time being while it searches for a successor. He will then remain at the company until September 2020 as an adviser, presumably to ensure the transition proceeds smoothly.

Although it has had its ups and downs over the years, Western Digital has largely performed well under Milligan, who oversaw its record-breaking $19 billion acquisition of rival storage firm SanDisk Corp. in 2015.

News of Milligan’s departure came as Western Digital reported fiscal first-quarter results that beat expectations, only to follow up with weak second-quarter guidance that came in below Wall Street’s estimates.

The company reported a profit before certain costs such as stock compensation of 34 cents per share on revenue of $4 billion. That was better than expected, with Wall Street having forecast a 30-cent profit on revenue of $3.93 billion.

Western Digital still posted a net loss of $276 million for the quarter, however, which was in stark contrast to the $511 million profit it recorded in the same period a year ago.

The bad news is the unprofitable spell is likely to continue, as the company projected second-quarter revenue of $4.1 billion to $4.3 billion, bracketing Wall Street’s estimate of $4.22 billion.

“It’s a hard time for traditional IT providers and Western Digital is no exception,” said Holger Mueller, principal analyst and vice president of Constellation Research Inc. “Transformation and adoptions to new markets, customer demands and competitive pressure can make it hard to thrive for these vendors. Let’s see if new leadership can reinstate Western Digital to its former glory.”

It’ll be hard pressed to do that no matter who takes over. WD’s stock fell by almost 10% in the after-hours trading session as investors decided the uncertainty was all a bit too much.

Nonetheless, Milligan insisted that Western Digital’s fiscal 2020 was “off to a good start.”

“The overall demand environment remains solid,” he said. “We continue to believe the flash industry has passed a cyclical trough, with improving trends across our flash product portfolio.”

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