The surest way for investors to maximize their return-generating potential is to extend their holding periods. While stocks tend to wiggle up and down over short time frames like quarters or years, their track records are more uniformly positive when pushed out to decades.

With that bigger picture in mind, let's look at a few quality stocks investors might look back on in 20 years and be glad they purchased today. Read on for some good reasons to consider buying lululemon athletica (NASDAQ:LULU) and McCormick (NYSE:MKC).

1. Lululemon Athletica

It's no secret on Wall Street that Lululemon is an attractive business. The yoga-inspired apparel retailer has trounced its growth outlook for six consecutive quarters as it races toward $4 billion in annual sales -- and shares have soared in response to the good news. But the chain is exposed to a few trends that could lift its results far above that mark over the coming decades.

A yoga class holding a pose.

Image source: Getty Images.

E-commerce ranks high on that list. Lululemon already counts a quarter of its business from this direct-selling channel, but that proportion could easily expand to over 50% in time. This shift played a key role in pushing gross profit margin up 7 percentage points since 2012 to 53% of sales. CFO Patrick Guido is predicting plenty more gains along those lines in fiscal 2019 and beyond.

Then there's Lululemon's international growth prospects. When you consider that the Chinese market alone provided an additional $1 billion of sales for rival Nike just in 2018, it seems plausible that Lululemon can meet its goal of quadrupling overall international sales by 2023, even as it pushes into new niches like men's clothing and outerwear.

2. McCormick & Company

It's impossible to predict what consumer food tastes will be in 20 years. But whatever they are, McCormick will likely be a leading force in the industry both for home cooks and for restaurant chains. The packaged food giant has been an industry staple for over a century, after all, and its portfolio of franchises, from McCormick herbs and spices to Old Bay seasoning, routinely outgrows the wider industry. Sales jumped 12% in fiscal 2018 while peers like Campbell Soup and General Mills struggled with near-zero growth.

Growth is slowing in 2019 to around 4% as the company has now fully incorporated the 2017 purchase of the French's and Frank's condiment brands. That's below management's long-term goal of roughly 5% annual sales gains, but CEO Lawrence Kurzius and his team believe they'll move back toward that target in 2020 and beyond. Meanwhile, investors who hold this stock can look forward to improving profitability that should support earnings growth of almost 10% each year.

McCormick's strong cash flow will deliver increasing dividend payments, too, while providing management with enough capital to resume stock repurchases in 2020 and perhaps begin hunting for the next game-changing acquisition that could make use of the company's unique global sales footprint. Steadily reinvesting those dividends could supercharge investor returns over the coming years and decades.