(Reuters) - Apple Inc said on Tuesday that retail chief Angela Ahrendts will leave the company in April after five years on the job, the third departure of a retail head brought in from outside the company.

The tech giant, which is known for its long-serving top executives, did not give a reason for the departure. It comes as Apple tries to reverse a slide in sales of its iPhones.

Ahrendts, who is among Apple’s highest-paid executives, came to the company in 2014 after being chief executive of fashion retailer Burberry Group Plc .

During her tenure, the company redesigned its retail stores with an emphasis on Apple’s appeal as a luxury brand and opened locations in pricy districts such as a glass-walled store on Chicago’s Michigan Avenue last autumn.

Ahrendts undertook some controversial moves, such as removing the formal Apple “Genius Bar” for technical service from stores and setting up more casual service centers instead. The introduction of a “Genius Grove” of potted plants at Apple’s flagship San Francisco location generated some complaints about customer service.

She also cut the number of outside companies selling accessories such as phone cases in Apple’s stores, dedicating the space to Apple’s own, generally more expensive, accessories.

Apple has long leaned on outsiders for help running its stores since former CEO Steve Jobs tapped Ron Johnson in 2000 to build Apple’s retail operations. By the time of his departure a decade later, Apple had a string of stores that were the envy of the shopping industry, generating sales per square foot that rivaled luxury jewelers.

Apple briefly tapped British retail executive John Browett to run its stores before hiring Ahrendts. In her five years in the post, she presided over only modest growth in the number of locations, expanding from 437 stores in Apple’s fiscal 2014 to slightly more than 500 today, but she renovated many older locations.

Ahrendts made $26.6 million in Apple’s fiscal 2018, more than Apple CEO Tim Cook but on par with the compensation of other senior executives. Her tenure was relatively short compared to executives such as services chief Eddy Cue, Chief Operating Officer Jeff Williams or marketing chief Phil Schiller, each of whom has worked at Apple more than 20 years.

Apple named human resources chief Deirdre O’Brien as senior vice president of “Retail + People” to replace Ahrendts. O’Brien has worked at Apple for more than 30 years.

Last month, Apple disclosed the first-ever decline in holiday season sales of the iPhone since the device’s introduction more than a decade ago. It also warned investors that sales for the current quarter were likely to be lower than Wall Street expected.