At the 2016 Daily Journal Meeting, Charlie Munger discussed the importance of keeping an open schedule:

There’re two things that Warren and I have done and Rick Guerin has done, too, to a considerable extent. One is that we spend a lot of time thinking. Our schedules are not that crowded. We look like academics more than we look like businessmen.

Our system has been to sift life for a few opportunities and seize a few of them. We don’t mind long periods in which nothing happens. Warren is exactly the same way. Warren’s sitting on top of an empire now. You look at his schedule sometime and there’s a haircut.

Tuesday, haircut day.

That’s what created [one of the] world’s most successful business records in history. He has a lot of time to think.

Source: Shane Parrish (of farnamstreetblog.com) on Medium