Time Warner Cable (UNKNOWN:TWC.DL) -- supplier of cable TV, video, data, and other communication services to more than 15 million subscribers -- has posted four straight quarters of rising revenue. Most recently, the company reported year-over-year income growth of over 10% for its second quarter. Shares of the company have responded well to all the good news, up 16% year to date.

However, there are a few headwinds, particularly questions about TWC's expected merger with Comcast Corp. (NASDAQ:CMCSA), intense competition within the space from companies such as DISH Network (NASDAQ:DISH), and, most recently, technological glitches such as last month's massive outage, reminding us that the company's technology isn't perfect. Let's look further at those three reasons that Time Warner Cable stock could still fall.

Image source: Comcast.

1. The fate of the merger with Comcast remains unclear
TWC and Comcast announced their plans back in February to merge under the Comcast name. Shares of Time Warner Cable held at that time would be converted to 2.875 shares of CMCSA, which places a current value on TWC of about $163 per share. With the stock currently around $155, that conversion would provide a small, tax-free gain for current Time Warner Cable shareholders.

Comcast stock has had a good year, too, with Q2 income up over 10% and EPS up more than 16% year over year. Given the solid performances from both companies, and the potential for increased market share, a merger would seem to be a combination of strengths.

But there's no guarantee that a merger will happen. It could hit a road block in the FCC over competition concerns, especially as FCC Chairman Tom Wheeler has already expressed concerns over the lack of U.S. residential broadband competition. Other companies, including DISH, have also been lobbying to have the merger rejected.

The potential for a merger has helped boost TWC stock, but it could take a hit if the merger fails.

2. Competition is strong
TWC isn't the only company in its industry doing well right now. If the Comcast merger fails, then Comcast remains a rival in a highly competitive industry. The same holds true for DISH Network, which already offers more entertainment options than TWC does -- including access to some Sirius XM channels -- and has its own acquisition targets in mind. If DISH ends up acquiring T-Mobile US, it could prove to be an attractive investment alternative to TWC. So could Comcast if the companies remain separate. In either case, TWC could see its stock price fall.

3. Last month's outage is a reminder of an imperfect technology
Millions of TWC subscribers across 29 states lost service for about three hours in August. The outage was blamed on a technical glitch during routine maintenance, but that doesn't mean customers weren't upset. Government officials in New York even called for an investigation.

Even though this kind of outage isn't a regular occurrence for TWC, it was a strong reminder that the technology isn't perfect and that companies must constantly prove their quality to stay near the top of their industries. The problem was quickly fixed and the stock didn't suffer, but continued outages down the road could damage TWC's reputation and even send customers looking for alternatives, such as DISH.

Foolish takeaway: Despite potential downfalls, the long term looks good
With solid Q2 earnings and many reasons to believe the company can continue driving long-term growth, Time Warner Cable looks like a strong investment choice. Competition is tough, but TWC continues to advance its technology and gain subscribers, all while it quickly fixes service interruptions. This company looks like a good long-term play whether that's as TWC or as part of CMCSA. Investors should feel confident about its prospects, with or without a merger, but it's wise to be aware of the short-term challenges.

Bradley Seth McNew owns shares of Apple. The Motley Fool recommends and owns shares of Apple, Google (A and C shares), and Netflix. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.