Marks & Spencer has ousted its clothing and home boss, Jill McDonald, who spent two years attempting to turn around the struggling division.
Chief executive Steve Rowe will take over from Ms McDonald in the short term.
He said the firm needed to "address long-standing issues in our clothing and home supply chain around availability and flow of product".
Ms McDonald had previous senior roles at Halfords and McDonald's.
"Her lack of skill in clothes buying and supply chain appears to be the problem. But then the problem existed before she joined, didn't it?" Global Data retail analyst Maureen Hinton tweeted.
Ms McDonald joined Marks & Spencer in autumn 2017 as it began a major turnaround plan, which has seen it shut stores and revamp its management.
Jill McDonald's appointment came as a surprise.
The former boss of Halfords had been parachuted into one of the trickiest jobs in retail with no fashion experience.
We were told she'd been hired for her "first-class customer knowledge" and experience in running high-achieving teams. In the end, that wasn't enough.
Marks & Spencer still hasn't fixed the basics when it comes to its all-important clothing business.
Availability, for instance, is still a big issue. It's clear she hasn't been able to move quickly enough to tackle its long-running problems.
Now chief executive Steve Rowe has taken direct control of this division again until a successor can be found.
Despite the turnaround plan, profits have continued to fall, and Mr Rowe said this week that it had been a "troubled year" for the company's vital clothing and home division.
At the firm's annual general meeting on Tuesday he listed major failures, including not buying enough jeans for a February promotion.
"That led to us having some of the worst availability in casual trousers I've seen in my life," he said.
However, he also said clothing ranges had improved in terms of fit, style and value.
"Further work [is needed] on getting size ratios correct, making sure we reduce the number of lines we're running [and] concentrating on the big lines that we're famous for across the UK," he added.
Mr Rowe said Marks & Spencer had developed a strong team in clothing, praising Jill Stanton, women's and children's director, and Wes Taylor, the menswear director, who were both hired in 2018.
However, he did not mention Ms McDonald's name.
After several failed re-launches over the past decade, the 135-year-old M&S is facing challenges to its clothing business from fast-fashion chains such as Zara and H&M.
In May M&S reported its third drop in annual profit in a row, and a 1.6% fall in clothing and home like-for-like sales. Its shares are down 30% from a year ago.
Announcing Ms McDonald's departure from the business, Mr Rowe said she had "recruited a talented team, improved the quality and style of product and set a clear direction for the business to attract a younger family age customer".
Ms Hinton told the BBC that Marks & Spencer clothing had been losing market share for years, so whoever takes the division on next "faces a real challenge".
"Even those before [Ms McDonald] with a strong clothing background could not attract back shoppers who have deserted it for other retailers and brands that have far more enticing ranges and stores," she said.
Marks & Spencer's management knew Ms McDonald had no fashion experience when they hired her, Ms Hinton said.
"You would have thought there would be the experience and support in the business to make up for her lack in this area," Ms Hinton said.
"But it seems not - which is even more worrying as these are described by Marks & Spencer as longstanding issues," she added.