If you fast-forward through the years, there was a period of time when there was too much debate inside the company about the significance of e-commerce, there were leaders who believed it would never be any bigger than the catalog business, there were leaders that believed it would never be profitable.

There've been times when leaders have to make decisions, and if you had read my 360 when I first started as a CEO, it would've repetitively said, "You take too long to make decisions, you're participative and that's good, but you need to move faster, be decisive." And as the years went, that stopped being on my 360 because I think I got more confident and more self-aware that sometimes decisions just needed to be made.

One of my predecessors is said to have observed that in making his decisions he had to operate like a football quarterback - he could not very well call the next play until he saw how the last play turned out. Well, that may be a good way to run a football team, but in these days it is no way to run a government.

The only thing I really think about is: How are we making decisions and getting things done such that Walmart is succeeding and creating value 50 years from now?

The one thing I have learned as a CEO is that leadership at various levels is vastly different. As you move up the organization, the requirements for leading that organization don't grow vertically; they grow exponentially.

When I was president of the company, I said, 'Okay, I can do this - piece of cake.' Then when you are the CEO, the responsibilities multiply enormously because you worry about everything.