Amazon CEO Jeff Bezos announces Blue Moon, a lunar landing vehicle for the Moon, during a Blue Origin event in Washington, DC, May 9, 2019.

Jeff Bezos has gone through a lot of changes since Amazon's IPO in 1997 — most notably in his appearance and level of wealth. But there's one thing that's remained constant: his relentless focus on the future.

That approach, which Bezos touted in his first letter to investors 22 years ago, was made abundantly clear this week in Amazon's second-quarter earnings report. Amazon beat Wall Street estimates on revenue but missed on profit, mostly because of increased spending across the board, a pattern that's continuing.

"The investment will be stepping up in 2019," Amazon CFO Brian Olsavsky said during the earnings call on Thursday.

Shipping costs accelerated 36%, the highest in five quarters, to $8.1 billion, after the company spent more than the projected $800 million to make one-day delivery the standard for Prime members. In other words, Amazon is cutting into its profit margin today so it can send more things faster and, if the thesis works, lure even more consumers into Prime.

Amazon shares fell close to 2% on Friday following the disappointing earnings number. But the stock is still up 29% this year, and Amazon remains the world's second most valuable publicly traded company, behind only Microsoft.

Here's what Bezos wrote in his 1997 shareholder letter — shortly after the company's IPO — which has been included in every annual letter as a reminder of what's important:

"We will continue to make investment decisions in light of long-term market leadership considerations rather than short-term profitability considerations or short-term Wall Street reactions," Bezos wrote in the letter at the time.