Amazon.com Inc’s sales projections for the crucial holiday quarter disappointed, and third-quarter results missed Wall Street’s targets, sending the online retailer’s shares 9 percent lower. The company projected on Thursday net sales of between $27.3 billion and $30.3 billion for the holiday quarter, lagging the $30.89 billion analysts had expected on average. After an unusually busy first half of the year that saw the online retailer spend on developing everything from mobile phones and Hollywood-style production to grocery deliveries, investors were ready to see it curtail its ambitions somewhat and start delivering sustainable profits.