I first heard this saying a few years back from Joe McCannon of the Institute for Health Improvement, who was campaign manager for an amazing effort by this non-profit to reduce the number of preventable deaths in U.S. Hospitals. It was called the 100,000 Lives Campaign, which according to most experts who have looked at the data, probably did reduce 100,000 preventable deaths as a result of implementing simple evidence-based practices like hand-washing and keeping the bed elevated about 45 degrees for patients on respirators. Huggy Rao and I have written about the campaign in the McKinsey Quarterly if you want to read more.
I was quite taken with Joe's use of that expression and emphasis on logistics and the campaign he led did have a grand strategy and a big hairy goal. But big hairy goals don't mean much without thousands of small wins. My colleague Jeff Pfeffer and I have argued for years that implementation, not strategy, is what usually separates winners from losers in most industries, and generally explains the difference between success and failure in most organizational change efforts, sales campaigns and so on. I also believe (and wrote here) that one of the dangers of talking about leadership versus management is that the implication is that leadership is this important high status activity and management is the shit work done by the little people. My view (and there is plenty of evidence to support it) is that effective management -- the work done by the collection of bosses and their followers in an organization, if you will -- is probably most crucial to success. After all, they are the people who turn dreams into reality.
P.S. There is also another possibility. It could be that strategy is very important to the success of firms, but it does not explain differences among firms in an industry because following the right strategy is required to stay alive and that executing strategy explains the differences in performance among living firms. In other words, all the firms that followed the wrong strategy are dead -- which I think is a reasonable and quite plausible explanation and is supported by some research in a subfield of organizational studies called population ecology.