This article is part of our Rising Stars Portfolio series.

Last December, I bought shares of Costco (Nasdaq: COST) for my Rising Star portfolio. A major part of my investing thesis was that Costco is a gold standard company that treats its various stakeholders well. Yesterday, the warehouse retailer further confirmed that rosy opinion by announcing a dividend hike and share buyback.

Some people perceive dividends as votes of confidence. One writer for Investors Business Daily recently interpreted "bold" dividend hikes from the likes of Wynn Resorts (Nasdaq: WYNN), PNC Financial Services (NYSE: PNC), and Ingersoll-Rand (NYSE: IR) as signs of an upbeat economic outlook. That may be true, but dividends and buybacks don't guarantee impending financial success.

In years past, now-bankrupt Borders paid a dividend, even with its finances on the brink of ruin. And plenty of the financial companies that received TARP funds were required to suspend their own dividends. In March, the Federal Reserve even rejected Bank of America's (NYSE: BAC) request to institute a "modest" dividend hike in the second half of the year. Apparently, the Fed didn't share B of A's confidence in its own health.

IBM (NYSE: IBM) recently increased its dividend by 15%, to $0.10 per share, and approved buying back $8 billion of its stock. However, with IBM shares trading at a new 52-week high, investors may wonder whether that buyback will give the company the most bang for its buck. IBM also has a debt-to-capital ratio of 57%. Paying down some of that debt might prove a better use for the company's cash.

Of course, one could make a similar argument about Costco, which also hit a new 52-week high yesterday, amounting to a 16% return since I bought it for my Rising Star portfolio. That new infusion of bullishness likely related to its 17% dividend boost, to a quarterly $0.24 per share, and the approval of a new $4 billion share buyback program. Still, Costco's debt-to-capital ratio is a far more manageable 15%, and its business has been firing on all cylinders lately.

Regardless, I don't love Costco because it pays a growing dividend. I admire it as a best-in-class company with a solid management team that's building a long-term business. Costco's increased dividend is great news, and it certainly gives stockholders even more reason to love the stock. However, I'm even happier about the positive dividend I get from knowing that by investing in Costco, I own a piece of a truly great business.

This article is part of our Rising Star Portfolios series, where we give some of our most promising stock analysts cold, hard cash to manage on the Fool's behalf. We'd like you to track our performance and benefit from these real-money, real-time free stock picks. See all of our Rising Star analysts (and their portfolios).