At the Daily Journal Corporation Annual Shareholders’ Meeting 2018 (14-Feb-2018,) Charlie Munger opined about how Warren Buffett and Charlie Munger changed their minds about investing in railroads and airlines for Berkshire Hathaway:

For a long time, Warren and I (painted over) the railroad because there were too many of them, and it was too competitive, and union rules were too crazy. They were lousy investments for about 75 years. And then they finally…the world changed and they double decked all the trains and they got down to four big rail systems in all the United States in terms of freight and all of a sudden we liked railroads. It took about 75 years. Warren and I never looked at railroads for about 50 years, and then we bought one.

Now airlines, Warren use to joke about them. He’d say that the investing class would have done better if the Wright Brothers would never have invented flight. But given the conditions that were present when the stock was purchased and given the conditions of Berkshire Hathaway where it was drowning in money, we thought it was ok to buy a bunch of airline stocks. What more can I say? Certainly it’s ok to change your mind when the facts change. And to some extent the facts had changed, and to some extent they haven’t. It is harder to create the little competing airlines than it was. And the industry has maybe learned something. I hope it works better, but I don’t think its…I think the chances of us buying airlines and holding them for 100 years is going to work that well. I think that’s pretty low.

Source: Charlie Munger aficionado Richard Lewis’s thorough transcript at his Lattice Work Investing blog.