Warren Buffett says

“Wide diversification is only required when investors do not understand what they are doing.”

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“No business can continue to shrink. That can only go on for so long before irrelevancy sets in.”

“If you’re long-term oriented, customer interests and shareholder interests are aligned.”

“Why focus on cash flows? Because a share of stock is a share of a company’s future cash flows, and, as a result, cash flows more than any other single variable seem to do the best job of explaining a company’s stock price over the long term.”