The 80/8 Rule

Shane Wilson points us to  Jim Barnes who quotes James Allen, Frederick F. Reichheld and Barney Hamilton, The Three "Ds"
of Customer Experience, Harvard Business School Working Knowledge:

A study by Bain & Company found that 80 percent of companies surveyed believed that they delivered a "superior experience" to their customers. But, when customers were asked to indicate their perceptions of the experiences they have in dealing with companies, they rated only 8 percent of companies as truly delivering a superior experience