Shares of tech-giant Apple (AAPL -1.10%) have a long track record of rewarding investors. In fact, the stock has outperformed the S&P 500 by a wide margin over the last 10-, five-, three-, and one-year periods. But can the tech giant keep delivering outperformance over the next decade?

A close look at the stock and, more importantly, the underlying business suggests there's likely more meaningful growth to come for Apple shareholders. Here are four reasons there's a high probability of Apple stock performing well over the next decade.

1. Apple boasts a powerful "engine" of loyal users

Much of the analysis of Apple stock in the media is focused on the iPhone. This, of course, isn't surprising. The iPhone accounts for over half of the company's annual revenue and is obviously imperative to the business.

But the real driver for Apple's business is the user behind the iPhone. The company's efforts to consistently deliver an integrated ecosystem of hardware, software, and services that delight customers have helped the company not just sell products, but also build a loyal base of customers across many actively used devices (more than 1.8 billion as of the last time Apple reported the figure).

Pairing this installed base of active devices with the company's growing services business (sales from both native and third-party apps, cloud storage, AppleCare, and similar offerings), Apple boasts what management has been increasingly referring to as its "engine." An active base of loyal subscribers, which reached a record high in the company's most recently reported quarter, represents a monetization opportunity for the company as Apple works to increase customer engagement over time.

This engine gives Apple a reliable stream of revenue in its services business that will likely grow for the foreseeable future.

2. The tech giant is more focused than its megacap peers

Second, Apple's business is very focused, compared to some megacap peers. Amazon, for instance, seems to have its hands in almost everything, including online store revenue, private-label products across all sorts of categories, various tech devices, streaming TV and music services, cloud computing, grocery stores, and much more. Meanwhile, the beauty of Apple's business is easily articulated through nothing more than its product segments: iPhone, Mac, iPad, services, and "wearables, home, and accessories," which largely consists of earphones, headphones, and voice-activated speakers.

The smaller base of products today means the company can focus its resources across just a few product lines to ensure they're as high quality and marketable as possible.

3. Apple manages its capital prudently

The tech giant also has a reputation for being a good capital allocator. Consider that the company has repurchased more than $550 billion worth of its own stock at an average purchase price (on a split-adjusted basis) of just $47. As Apple Chief Financial Officer Luca Maestri noted in the company's most recent earnings call, the program "has been incredibly successful." Adding to its capital-return efforts, the company has paid out a dividend since 2012, increasing it every year.

In addition to its value-creating capital-return program, the company is known for being a penny-pincher when it comes to acquisitions, decreasing the risk of Apple overspending on assets. Apple's largest public acquisition was Beats Electronics for $3 billion in 2014.

Even back then, however, this was a drop in the bucket for the company. Of course, Beats ended up playing a role in the launch of AirPods, which has been a wildly successful product line.

4. The stock's valuation is attractive

Finally, the tech stock currently has an attractive valuation. Trading at just 23 times earnings at the time of this writing, Apple stock is cheaper on a price-to-earnings basis than both Proctor & Gamble and McDonald's. For a company with a highly focused business, a loyal customer base, and a long history of exceptional capital allocation, this valuation is approaching bargain territory.