Out-of-patience investors sell off Amazon

Amazon has long acted like an ideal customer on its own website: a freewheeling big spender with no worries about balancing a checkbook. Investors confident in founder and CEO Jeff Bezos' invest-and-expand strategy flooded into the stock as the company revolutionized shopping, upended the book industry and took on the cloud—even though its vast range of initiatives ate up all the company's profits.