Many of the theory’s exemplary cases did not fit four of its key conditions and predictions well. A handful corresponded well with all four elements (notably, for example, the disruptions by Salesforce.com, Intuit’s QuickBooks, and Amazon.com). However, a majority of the 77 cases were found to include different motivating forces or displayed unpredicted outcomes. Among them were cases involving legacy costs, the effect of numerous competitors, changing economies of scale, and shifting social conditions. Discussions with our industry experts also helped us to identify the most generally applicable elements of the theory of disruptive innovation as well as to define other ways managers can guide businesses through stormy times.
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Before surveying and interviewing experts on each of the 77 cases, we identified four key elements of the theory of disruption: (1) that incumbents in a market are improving along a trajectory of sustaining innovation, (2) that they overshoot customer needs, (3) that they possess the capability to respond to disruptive threats, and (4) that incumbents end up floundering as a result of the disruption.
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In summary, although Christensen and Raynor selected the 77 cases as examples of the theory of disruptive innovation, our survey of experts reveals that many of the cases do not correspond closely with the theory. In fact, their responses suggest that only seven of the cases (9%) contained all four elements of the theory that we asked about.