Apple's (AAPL -0.82%) stock recently pulled back following the company's release of its third quarter earnings due to a slight miss on iPhone sales and soft sales guidance for the current quarter. I personally think that Apple's low valuations still make it a compelling buy at current prices, but one Apple insider has sold a lot of shares recently.

According to SEC filings, retail chief Angela Ahrendts has sold $19.5 million in Apple stock since April. Ahrendts notably sold $8.7 million in shares in three separate transactions right before the Apple Watch launch on April 24. We shouldn't jump to conclusions based on those transactions alone, but we should dig deeper and see what they actually mean for Ahrendts and Apple's investors.

Apple's highest-paid employee
When Apple initially hired Ahrendts, Burberry's CEO, as its retail chief in October 2013, it indicated that it wanted to reinforce its luxury appeal. Preserving that premium appeal allows Apple to sell mid-tier hardware at premium prices, which helped it gobble up 92% of the world's smartphone profits during the first quarter with an 18% market share, according to Canaccord Genuity analyst Mike Walkley.

With estimated earnings of $82.6 million last year, Ahrendts became Apple's highest-paid employee and the highest-paid woman in America. About $70 million of that package consisted of stock awards, with $37 million listed as compensation for the stock bonuses she gave up at Burberry. In that context, selling $20 million in shares within a few months might not be such a huge deal.

Grading Ahrendts' performance
But investors might question whether or not Ahrendts deserves that massive paycheck. Her predecessor, John Browett, failed to fill the big shoes of Ron Johnson -- who pioneered the concepts of Apple Stores and the Genius Bar -- and was fired after just six months on the job. Browett tried to slim down Apple's retail stores by reducing employees and cutting costs, even as executives warned him that doing so could cause a customer service disaster during high-traffic product launches.

An Apple Store. Source: Apple.

Ahrendts is taking a different approach. Instead of shrinking Apple Stores down, she expanded Johnson's retail foundations and added pre-launch showcases for the Apple Watch in stores. Customers had to schedule "fittings", and customers who wanted to buy the gold versions of the watch were led to a private VIP room. One could argue that it was a pretentious strategy from Burberry's playbook for VIP customers, but it strengthened Apple's credibility as a luxury brand.

Ahrendts also sends out weekly video updates to all retail employees via an internal app. That personal touch has drawn positive comparisons to Ron Johnson, according to a survey of Apple employees by Business Insider. Ahrendts is also expanding Apple's online retail experience with an initiative known as "Customer at the Center", which encourages customers to order devices online instead of lining up at brick-and-mortar stores, which have more limited supplies.

Don't judge Ahrendts on the Apple Watch alone
The Apple Watch launch was Ahrendts' first big test as retail chief, but the device hasn't been selling as well as some analysts had hoped. Pacific Crest analyst Andy Hargreaves, for example, recently cut his 2015 sales forecast from 11 million to 10.5 million units, and his 2016 forecast from 24 million to 21 million units.

Some investors might link Ahrendts' recent stock sales with that "soft" launch, but they should remember two things. First, the Apple Watch was never intended to be the next iPhone or iPad. Second, Apple Watches claimed 75.5% of the global smartwatch market in the second quarter, according to research firm Strategy Analytics, with estimated sales of 4 million devices. Claiming three-quarters of the fledgling smartwatch market within three months certainly doesn't sound like a failure to me.

Apple Watch. Source: Apple.

It's also unfair to judge Ahrendts based on the launch of a single device like the Apple Watch. Instead, we should see how she handles the retail launches of the updated iPhones, iPads, and Macs later this year.

A final thought
In my opinion, investors should keep an eye on Apple's insider sales, but they shouldn't buy or sell shares based on those numbers alone. Angela Ahrendts certainly sold a lot of stock lately, but it's arguably reasonable compared to her overall pay package. Insiders also have plenty of personal reasons to sell, which aren't revealed in SEC filings.

Between fiscal 2006 and 2013, Burberry's annual sales growth rose from the low single-digits to the high teens. That growth was widely credited to Ahrendts' strategy of introducing new lines for younger shoppers while protecting the premium appeal of its classic check pattern. If Ahrendts can apply the same strategy to Apple's retail operations and keep its top devices fresh in both online and brick-and-mortar settings, then she certainly deserves to sell her shares whenever she wants.