The big picture: In the ten years he's been CEO of Apple, Tim Cook has propelled the company to new heights and overseen the development and launch of several successful products. Cook celebrated his 60th birthday last year and is likely looking into succession planning, which has led to a lot of speculation about when he might retire. Some say this could be as early as 2025, or right after Apple launches another major product category.

Earlier this year, Tim Cook said during an interview with Kara Swisher that he probably wouldn't be at Apple in 10 years, but he didn't give any hints as to when he might step down from his position or who would be the candidates that could replace him as CEO of Apple.

However, as Bloomberg's Mark Gurman notes in this Power On newsletter, there is a good possibility that Tim Cook is simply waiting to oversee one major new product category before he proudly steps down from his current role.

In the ten years he's been CEO, Cook transformed Apple into a $2.5 trillion tech giant that is also the most valuable company in the world. Quarterly revenue has grown to over $110 billion, and profits have more than quadrupled to just under $29 billion. The company today has 147,000 full-time employees and makes an average of $10,000 every second, with more than a third of that representing profit.

So far, Cook has overseen the development and launch of several Apple products, including the Retina MacBook, iPad Pro, iPhone X, Apple Watch, AirPods, and Apple TV 4K. All of these were successful, but most were more evolutionary than revolutionary, while others benefitted from being among the best accessories for these successful products.

Gurman believes Cook is currently devoting most of his attention to the release of Apple's highly anticipated mixed reality headset, as well as a pair of augmented reality glasses, both of which are expected to land before the middle of the decade. And since Cook has a pay deal that runs out in 2025, he may retire sometime between 2025 and 2028.

Apple has also been working on a car and experimenting with autonomy as a "core technology," but that's likely more than a few years out. The company's augmented reality ambitions have already materialized to a small degree through the iPhone and iPad, while the car project is nebulous at this point.

As for who is set to replace Tim Cook as CEO of Apple, the company is likely eyeing a tech or operations executive for the role, which means there are several potential candidates. And while some, like Craig Federighi, look like they're more suited to their current role, others like Jeff Williams, Deirdre O’Brien, and John Ternus look like good long-term successors for Cook.