Charlie Munger said at Daily Journal 2019 Annual Shareholders’ Meeting,

Part of our secret is that we don’t attempt to know a lot of things. I have a pile on my desk that solves most of my problems. It’s called the too-hard pile. And I just keep shifting things to the too-hard pile. Every once in a while, an easy decision comes along and I make it. That’s my system. Everything in the too-hard pile, except for a few easy decisions which I make promptly.

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We’re just trying to have that uncommon sense I’m talking about. And part of our uncommon sense is just to refer a lot of stuff to the too-hard pile.