"The longer you're here, and the more you build, and the more you collaborate, the more you become personally passionate about our mission," says Mike Bundy, who started out in a temp job stacking pallets at Amazon's first fulfillment center in 1997. Today, he manages a 300-person software organization. "I feel like a founder of the company. I feel a great deal of personal pride in what we’ve done."

In his fulfillment center days, when Amazon still had a lot of technological growing pains, Mike was always the guy popping into the tech room to ask, "How can we help?" His curiosity and commitment led to relationships with mentors who helped him follow his newfound passion and transform himself from an art-school grad into a leader of projects that truly reinvent the customer experience.

It's easy to forget these days, but there was a time when Amazon didn't – and couldn't – promise that an order would arrive by a certain date. Mike helped change that. "We totally overhauled the way we make promises on the website," he says. "We got rid of the 'usually ships in 24 hours' messaging. We developed the capability to make these aggressive delivery estimates and keep them. In many ways, this was what Prime was born of."

By the end of 2011, Mike got promoted to the role of director and managed a team working on software for Amazon's fulfillment centers, the state-of-the-art versions of where Mike first worked. "So for me, that was like coming back to where I started," he says. "It was super exciting."

One of Mike's Amazon mentors taught him that "the bottom line is total ownership. There is no problem you don't own, and you've got to dive deep on them all, and you've got to move really fast."

For Mike, who got married and became a dad during his almost two decades at Amazon, ownership isn't just about getting work done; it's about leaving work behind and recharging with family. "I manage my schedule really aggressively," he says. "If you let your calendar get filled up with non-essential stuff, you're not owning your career, and you're not owning your path. You can be scrappy. You can be entrepreneurial. You don't have to give up your personal life."