The idea of excessive diversification is madness. We don’t believe that widespread diversification will yield a good result. We believe almost all good investments will involve relatively low diversification. If you took our top fifteen decisions out, we’d have a pretty average record. It wasn’t hyperactivity, but a hell of a lot of patience. You stuck to your principles, and when opportunities came along, you pounced on them with vigour. Berkshire in it’s history has made money betting on sure things.

Charlie Munger