One industry that I play close attention to is the airline industry - not so much in terms of investing, but more about the customer service aspect of the industry and how service affects stock prices. Awhile back I asked if you would invest in the airlines and I still stand by word that all airlines think about is the bottom-line - meaning I still won't invest in them.

However, I was curious to see whether or not the airlines would be a good investing choice, so I did a search to see. I came across this Motley Fool article that says Warren Buffett is skeptical about making money with the airlines. That's enough of a reason for me to say, "No, thank you!" to investing in the airlines.

Although a majority of people do use the airlines to travel and it seems as if some airline companies are doing well (particularly United Airlines), it's still a pretty volatile industry and is closely tied to economic activity.

Then you have news of airline cancellations, as American Airlines experienced this week, which caused a huge drop in stock price. AMR Corporation (AMR), the parent company of AA, closed at $9.87 today. Here's a snapshot of what the stock looked like this past week...

The only way I would invest in an airline is if they made a 180 degree turn-around and put customer service (that includes internal customer service) as priority #1.