Four years ago, after enduring its second full-year earnings-per-share loss in the last three years despite 20% top-line growth, Amazon (NASDAQ:AMZN) bears questioned whether the e-commerce company could become a reliably profitable entity. Amazon underperformed the S&P 500 by 36 percentage points that year, falling 22% versus the 14% total return from the greater market.

Undeterred, CEO Jeff Bezos had other plans to grow the company's bottom line -- and those plans didn't involve e-commerce. In his 2014 shareholder letter, Bezos wrote that "Amazon Web Services (AWS) is growing big and fast," later adding: "Finally, I'm optimistic that AWS will have strong returns on capital." AWS has since provided the bulk of profits.

Read more at The Motley Fool.