When Jim Freeman, the Alexa VP in charge of messaging products, told Amazon he's leaving for the German e-commerce company Zalando earlier this year, the higher-ups asked him to stay, according to a person familiar with the matter.

Freeman didn't budge, and in April he ended up joining the Berlin-based company.

Freeman, who first joined Amazon 9 years ago and previously spent a short time at Zalando, had a lot of support internally, as he oversaw the development of all Alexa messaging features, like audio and video calling. Previously, he also ran Amazon's entire video team, including Prime Video and Amazon Studios.

Freeman's departure is part of a recent wave of executive departures at Amazon. Even as Amazon enjoys unprecedented success and record-level stock prices, some of its senior executives are opting to leave. Smaller companies offer fresh opportunities and a relief from its high-intensity work culture, hiring experts say.

More than a dozen executives and senior managers have left Amazon over the past 10 months. Among them, Susan Harker, a VP responsible for global recruiting, took a leave of absence because of a family member's health issue, according to people familiar.

Other recent departures that have been previously reported include top executives like Prime boss Greg Greeley and marketplace chief Sebastian Gunningham, as well as lower-level execs like Gene Farrell, a VP at Amazon Web Services, and Tim Stone, a finance VP who joined Snap as CFO earlier in May. Mike George, former VP of Echo, Alexa, and the app store, retired last June after a 20 year-run at Amazon, but has rejoined the company, according to a person familiar.

In Freeman's case, this is his second run at Zalando. He had previously joined the company in 2016, only to return to Amazon six months later for personal reasons. The personal issue has been resolved in recent months, and so he insisted on returning to the German company, people familiar with the matter said.

In a statement, Amazon said, "It's simply incorrect to suggest that we have an executive retention issue. Amazon is the most attractive place to work in the US, according to LinkedIn, and we have nearly 95% retention among our Vice Presidents. For 20 years it's been the case that a handful of executives have come and gone — for personal or professional reasons — and that's true at any company. What's unique about Amazon is that many come back — we call them 'boomerangs'."