Shares of Apple (AAPL 0.64%) have recovered nicely in 2021 after a shaky start to the year, gaining more than 23%. What's impressive is that Apple has staged a comeback despite supply chain challenges that hurt its sales in the fourth quarter of fiscal 2021 (which ended on Sept. 25). In addition, investors have shown their faith in the tech giant even with weaker-than-expected guidance for the quarter that ends in December.

AAPL Chart

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As the chart above shows, Apple stock has gained momentum since the beginning of October. That's not surprising as the launch of the iPhone 13 gave investors a reason to cheer, with the device witnessing robust demand that outpaced supply. The company hasn't been able to make enough iPhones to meet the higher-than-expected demand as component shortages and coronavirus-driven shutdowns crippled production.

In an ideal world, this should lead to strong iPhone shipments in 2022 when the supply chain improves, boosting Apple's top and bottom lines and its stock price in the process. But that may not be the case, causing the stock to lose momentum early in the new year. Let's see why.

A person looking at a smartphone while sitting on a couch smiling.

Image Source: Getty Images.

Why Apple stock might fall next year

The iPhone is Apple's most important product. It produced nearly $192 billion in revenue for the company in fiscal 2021, which was just over 52% of its total revenue of $365.8 billion. Now, there are rumors that Apple may be losing customers due to its inability to make enough iPhones to satisfy demand.

According to a Bloomberg report, the company has reportedly told its component suppliers that the demand for iPhone 13 models has weakened as potential consumers aren't interested anymore in buying the device due to lack of availability. A survey carried out in Japan indicates that the number of existing iPhone owners interested in upgrading to the latest device is lower than last year when more people were interested in upgrading to the iPhone 12.

One of the reasons that may be the case is because of the long waiting times for the iPhone 13 Pro models, which are in stronger demand than the standard models. Third-party reports showed that the waiting time for the iPhone 13 Pro and the Pro Max ranged between 16 days and 23 days on Nov. 28. It is worth noting that Apple had reportedly reduced its 2021 iPhone 13 production target by 10 million units due to component shortages, which explains why its devices are still showing extensive waiting times.

The problem is that iPhone 13 delays are expected to last until February 2022, as reported by DigiTimes last month. These long waiting times and delays are reportedly causing customers to put off their iPhone 13 purchases. This isn't surprising, as the iPhone 13 will be nearly half a year old by the time it will be readily available for purchase in February next year.

This could lead customers to drop the idea of purchasing the iPhone 13 and instead go for the 2022 models. As a result, iPhone revenue could take a hit in the near term and weigh on the company's financial performance and stock price in 2022.

The stock could fly higher in the long run

Savvy investors, however, shouldn't worry about the potential short-term challenges Apple faces. Even if iPhone sales aren't as great as expected in the early part of 2022 due to problems out of the tech titan's control, one shouldn't forget the massive upgrade cycle that's driving Apple's growth.

According to IDC, Apple shipped 50.4 million iPhones in the third quarter of 2021, a jump of nearly 21% over the year-ago period. The company delivered this impressive growth during a quarter when the overall smartphone market contracted 6.7% year over year, with its biggest rivals Samsung and Xiaomi witnessing a contraction in their shipments.

What's more, Apple is enjoying a nice bump in the average selling price of each iPhone. Sales might be hamstrung by component shortages over the next few months, but it cannot be denied that the company is enjoying a mix of volume and price growth thanks to the adoption of 5G smartphones.

More importantly, there were more than a billion iPhone users at the beginning of 2021. Wedbush analyst Dan Ives pointed out in October that 25% of Apple's installed base of users haven't upgraded their iPhones in the past three and a half years, which means that there are at least 250 million users in an upgrade window who could buy the iPhone 13.

Additionally, the number of iPhone users without a 5G device is even higher since the first 5G iPhone went on sale just over a year ago. All of this indicates that investors shouldn't miss the forest for the trees as the iPhone juggernaut can continue rolling in the long run and the supply chain constraints would probably be just a bump in the road.

As such, Apple stock can eventually regain its mojo once it gets the production challenges out of the way in 2022 and ships more iPhones to customers. And this is just one of the reasons this tech stock could fly higher next year as it is working on more products that could accelerate its growth in 2022 and beyond. That's why it might be a good idea to buy the stock in case of a dip as the near-term challenges could eventually make way for long-term gains.