In Motley Fool’s MarketFoolery podcast on Dec. 30, host Chris Hill and Motley Fool One analyst Jason Moser received a question from a listener that basically said, What exactly is an investment thesis? How do you go about creating one? Attempting to simplify a concept that isn’t always cut and dry, Moser summed it up as either a long-term trend that’s playing out or a short-term event that may occur. His most helpful responses, however, came in the form of examples. On that note, here are two more examples — both based on my two largest holdings in my real money portfolio: Apple ( NASDAQ: AAPL ) and Tesla ( NASDAQ: TSLA ) .

But first, here is another interpretation of what an investment thesis is and how to create one — straight from my 10th grade English class.

Ms. Jones’ thesis

I’ll never forget the way Ms. Jones (I’ve used a different name for privacy) taught me to develop a thesis in the first paragraph of an essay. She described it as the bottom tip of an upside-down triangle.

Begin your opening paragraph broadly, she would say. Perhaps an interesting quote or intriguing fact that relates to your topic at a 10,000-foot view. Then narrow your writing until it hits a specific point — one powerful sentence that tells your reader the central idea your communicating.

Little did she know I’d use the advice for investing. I’ve found her approach to have many parallels to the way I develop a thesis for a stock. After I’ve done my research on a stock, both macro and micro, and I’m ready to make a decision about whether or not I want to invest in the stock, I apply her approach. It usually goes something like this:

1. Starting broadly, I ask: What are the big macro trends impacting this company and its industry?

2. How is this company poised within this trend?
3. What makes this company enduring (or not)?
4. Based on these developments and situations, what is the specific reason I believe this company is (or is not) worth its current price (the answer is my thesis).

Without further ado, here are two examples of theses (with a bit of background) developed using a similar approach as the one outlined above.

An investment thesis for Apple

The smartphone market is still growing rapidly. Worldwide smartphone shipments grew 38.8% in the third quarter from the year-ago quarter, according to IDC. Apple’s iPhone segment (its highest revenue and most profitable business segment) should benefit from this trend. As growth inevitably slows, Apple has built an army of lifelong customers who should prove to be a solid source of sustainable revenue over the long haul. Thanks to a very valuable brand, Apple’s products boast incredible customer retention from these customers. Importantly, these customers pay premium prices for Apple’s product; this has turned the company into a cash cow. Finally, Apple has consistently proven it has a strategy to jump from one new category to another, elegantly able to profitably cannibalize its innovations of the past.

My thesis: Even though Apple’s customers are as loyal as ever and its most important segments are still growing, Apple is priced for low single-digit growth. And healthy cash flow combined with a diligent plan to return cash to shareholders mitigates downside risk.