We all want to own winning stocks that can produce strong portfolio returns. But the reality is that not all investments perform as you hope. Ford Motor Company (F -1.65%) is one example.

In just the last two years, this top auto stock has fallen 16% -- and this was during a time that saw the S&P 500 rise 19%. It has seriously underperformed that broader index in the past decade, too.

Does this situation make Ford a once-in-a-generation investment opportunity right now?

Short-term optimism

Ford's latest financial results -- for the first quarter of 2024, which ended March 31 -- were a bit of a mixed bag. Adjusted earnings per share of $0.49 handily beat Wall Street analysts' estimates. However, that bottom-line figure was down 22% from the year-ago period. A production ramp-up and buildup of F-150 inventory was an important reason for this drop.

Total revenue inched higher by 3.1%. That can be viewed as a positive sign, particularly in today's environment of higher interest rates. Management highlighted improving volume and mix.

Digging beneath the headline figures, Ford's pro segment, which sells commercial vehicles, is the talk of the town. Sales and operating income here soared 36% and 120%, respectively, year over year.

On the other hand, the electric vehicle division, known as model e, was a huge disappointment once again. Unit shipments fell 20% compared to Q1 2023. However, because of weaker pricing trends across the industry, revenue tanked 84%. Even the dominant Tesla is struggling.

Nonetheless, management maintained its guidance of $10 billion to $12 billion for this year's adjusted operating income. And thanks to lower planned capital expenditures, the company expects to generate higher adjusted free cash flow in 2024.

Long-term pessimism

Despite what might appear to be a business on solid footing right now, at least according to the executive team's words, there is no shortage of reasons to be pessimistic about Ford. Investors should pay attention to some key factors.

Ford operates in an extremely competitive industry. You might argue that because of its long history which spans more than a century, Ford has developed a strong brand standing in the auto industry. I'm not so sure about that. There are numerous global brands that all have a robust presence on a global stage. This has prevented Ford from generating superior financial performance over the long term, which tells me that it lacks an economic moat on this front.

Speaking of financial performance, Ford leaves much to be desired. This is a very capital-intensive industry as building factories, investing in research and development, handling product warranties and recalls, paying a unionized labor force, and marketing to customers is incredibly costly. Ford has no choice but to play this game unless it wants to lose to rivals.

The result is consistently low operating margins. Even worse, this metric hasn't shown any ability to expand over time. Growth going forward also won't be anything to write home about anytime soon. Ford is a mature company whose revenue shouldn't rise more than GDP growth over time. Analyst estimates call for sales to increase at less than 2% per year over the next three years.

If those negative factors weren't enough to dissuade you from buying Ford shares, it's also important to realize that its business is sensitive to macro forces. If you had superpowers that allowed you to be able to forecast with consistent accuracy when the economy was headed toward a recession and when it was coming out of one, I have zero doubts that you could make a killing by trading this stock.

The issue, though, is that no one possesses that skill. This adds risk to the equation. So, although shares have traded down in the past couple of years, investors should think twice before adding Ford to their portfolios today.