Warren Buffett says

“There is no tougher job in corporate America than running an airline: Despite the huge amounts of equity capital that have been injected into it, the industry, in aggregate, has posted a net loss since its birth after Kitty Hawk. Airline managers need brains, guts, and experience—and”

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“It’s not possible for investors to consistently outperform the market. Therefore you’re best served investing in a diversified portfolio of low-cost index funds [or exchange-traded funds].”