In a recent interview on CNBC, Buffett said that Walmart CEO
Doug McMillon always carries with him a list of top 10 retailers of each of the past decades just to remind himself of the brutal history of retailing. Walmart took Sears to the cleaners and with status quo, there was a high chance Amazon and Costco will take Walmart to the cleaners. So far, they have done a pretty good job modernizing.
I turned down a job with them (mostly as I want to move back east and the job was only in sunnyvale, good location, just not for me at the moment). But the work they do is interesting, the compensation was competitive, and if you have a family some of their fringe benefits can be very valuable (employee discount at walmart, grocery delivery to the office could save lots of time...)
He means that why take small steps (such as eliminating greeters) and instead do every cost saving strategy possible much like Pepsi Co is doing now [1]