Shares of Best Buy (NYSE: BBY) have fallen 21% since peaking three months ago, and that's not the kind of direction you want to be heading in just ahead of a crucial financial update. He sees slowing industry growth, cost inflation, and difficult comparisons in key products weighing on near-term performance, justifying the former bull's shift to a neutral position on the stock. *Stock Advisor returns as of November 14, 2018 John Mackey, CEO of Whole Foods Market, an Amazon subsidiary, is a member of The Motley Fool's board of directors.