Innovation is not a big breakthrough invention every time. Innovation is a constant thing. But if you don't have an innovative company [team], coming to work everyday to find a better way, you don't have a company[team]. You're getting ready to die on the vine. You're always looking for the next innovation, the next niche, the next product improvement, the next service improvement. But always trying to get better.
If you've got a company that has a mentality inside that is filled with searching for a better idea every day, not just as a slogan but as a real concept, you will have innovation around you all the time.
What Sam Walton did was to go into one of the most mature industries of all and find a way to make it grow, grow, grow, double-digit, month after month, year after year. He did it by innovation, customer focus, and above all, speed.