Warren Buffett famously does not invest in airlines. However, the airline index is up 35% over the past quarter. Is Buffett wrong about airlines? In this video, Brendan Byrnes says no. Among the significant structural barriers that prevent airlines from being good long-term investments are fuel, labor, and other operating costs, along with a lack of competitive advantage and the cyclical nature of the business. There may be short-term runs in airline stocks, but for the long haul, these aren't great companies to be had at fair prices. Check out the video for further details.

Austin Smith and Brendan Byrnes have no position in any stocks mentioned. The Motley Fool recommends Southwest Airlines. 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.