There just aren't that many opportunities in the world that are that big, and for a company like Walmart that needs to move the needle in a big way, you have to take some big bets, but if you're going to take that much risk, the reward has to match up.

So growing ecommerce in the marketplace is key to being able to attract more advertisers. What we can do that some other people can't do is we can connect the dot between an ad you may have paid for digitally and a subsequent purchase in a physical store so that you can see the ad actually worked. So it too is an omni business for us.

We just have to pull all those threads together so that when you're experiencing us on the app, it's an unnatural act to go anywhere else because we've got the item and we've got it at the best price.

There are all these things that add up into this business that's Walmart that keeps it really interesting. At the root of it all, though, it's a people business and it's a merchandising business. Today, it's increasingly a technology business. The supply chain is critical, of course, and real estate still plays a key role.

I think real estate is really core, but you just nailed why I'm still here and loved retail - it's because of the breadth of it. I didn't appreciate how interesting retail was until I got started. You have to have a customer relationship, but you need leadership skills, servant leadership characteristics.

When you look at what was happening with e-commerce and how big that was going to become, there's the big wave of India, there's the big wave of e-commerce, and then there's the question of, "Is this the brand to invest in?". We developed this confidence in that team, and so far we've been proven to be right about that.