Walmart CEO Mike Duke is one of the most powerful men in business.
But as the leader of Walmart, America's largest retailer and employer, Duke is also one of the most controversial.
Throughout his tenure, Walmart has been criticized for paying workers low wages, not offering all employees healthcare, bribery scandals overseas and allegedly unsafe factory conditions.
Last night, Duke did a one-hour interview with the Council on Foreign Relations in New York.
When Dan Doctoroff, the president of Bloomberg LP, asked Duke his biggest regret, he said:
"When I look back, I wish we had moved faster. We've proven ourselves to be successful in many areas, and I simply wonder why we didn't move more quickly. This is especially true for e-commerce. Right now we're making tremendous progress, and the business is moving, but we should have moved faster to expand this area."
Duke has been CEO since February 2009.
While Walmart has made great strides improving its e-commerce business in the past year, the company is still lagging behind competitor Amazon for market share.
Walmart has tried aggressive new initiatives, including recruiting Silicon Valley talent, acquiring start-ups, pouring money into its mobile app and improving its search engine.
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