The long-term performance of tobacco giant Altria Group (MO 0.24%) has made many investors rich. Time after time, the company has overcome challenges, including legal, regulatory, and consumer advocacy efforts. Altria's pricing power and brand awareness have helped it stave off the downward impact of fewer numbers of people smoking, but even with the company's past success, there are still some dangers that could lead to Altria's stock price losing ground if things don't keep going well. Below, we'll look at three reasons why Altria investors might have to endure a falling stock at some point in the future.

Image source: Altria.

1. Altria's e-cigarettes, e-vapor products, and heat-not-burn alternatives to traditional cigarettes might not catch on.

Altria wasn't first out of the gate when it came to moving in the direction of alternative tobacco products. Competitor Lorillard, which has since merged with Reynolds American (RAI), took the lead with its blu eCigs brand, which it subsequently sold off as part of the terms of the Reynolds merger. Altria has since moved aggressively to catch up, with the company's Nu Mark subsidiary having made a huge marketing push to get its products into popular sales outlets like gas stations and convenience stores. Nu Mark aims to distinguish itself from other e-cigarette and e-vapor companies by using patented technology to develop superior products. Moreover, with access to premium brands, Nu Mark will have a natural advantage over some of its competition.

Yet one concern that investors should have is that the alternative products market is giving small companies a chance to market themselves as innovators, creating new pathways to entry that wouldn't be available to regular cigarette manufacturers. Like craft breweries in the beer industry or energy-drink specialists in the beverage market, small companies have a chance to catch up with bigger counterparts in the fast-rising market for e-cigarettes and e-vapor products. If that happens, Altria might not reap the full rewards from growth in that market.

2. An end to macroeconomic tailwinds could hurt Altria's customers.

Recently, Altria has benefited from a big boost in the spending power of average U.S. consumers. The plunge in crude oil prices since the end of 2014 has funneled through to the gasoline pump, and billions of dollars of discretionary income has been freed up for consumers to spend on other things. That has been a boon for Altria and the rest of the tobacco industry, especially because many people tend to buy their cigarettes at gas stations and therefore see the two purchases as directly aligned with each other. In addition, relatively low unemployment has helped push the U.S. economy higher, and although growth hasn't been at a breakneck pace, it nevertheless has been steady and reliable enough to make people more confident about their financial prospects and therefore willing to spend more.

For now, oil hasn't mounted a significant recovery, and gasoline prices remain near their lowest levels in more than a decade. Concerns about the sustainability of the U.S. economic recovery haven't turned into visible weakening. However, at some point, it's likely that discretionary spending will become more difficult for American consumers. When that natural cyclical downturn happens, Altria could find itself under pressure, at least temporarily.

3. Rising interest rates could draw attention away from dividend stocks like Altria.

One of Altria's most attractive features to investors is its stable income. The stock currently yields more than 3.6%, and it just announced an 8% dividend increase. The boost was the 50th time in 47 years that Altria has rewarded its shareholders with a rising quarterly payout.

Yet one of the reasons why investors have been so attracted to dividend stocks like Altria is that income-producing alternatives have largely seen their cash flows dry up. Interest rates on bonds remain near historic lows, and that has put income investors in a bind if they want to avoid taking on inordinate amounts of risk. Many have seen blue chip stocks like Altria as preferable to higher-risk corporate bonds.

Now, the Federal Reserve appears likely to push interest rates upward. If that happens, investors might respond by moving money back into the bond market, and that in turn could reduce Altria's appeal among shorter-term investors. Long-time shareholders have seen Altria's dedication to maintaining its dividend, but that won't preclude a possible knee-jerk drop in the share price when the Fed moves.

Altria has performed well, but even the best stocks suffer downturns from time to time. If these problems arise, shareholders should be prepared to see Altria stock take a hit for at least a short period of time.