Internal memos from Amazon executives explained the company's decision to lay off 16,000 corporate workers as necessary to become the "world's largest startup," according to the messages viewed by Business Insider. "Our ambition is to be the world's largest startup," Amazon executives wrote in two such memos viewed by Business Insider. "That means doubling down on a culture of ownership, speed, and experimentation — which requires us to continue evolving how we're structured."The "world's largest startup" ...