Rick Wallace shares the history of KLA-Tencor to show that it is important to follow one's business model. KLA revolutionized the industry by starting to charge for service instead of just offering it up for free. In order to enforce this, the founder had to risk losing IBM as a client. However, his bet paid off, and IBM finally agreed to pay for service. This has led to a large and profitable annuity stream for KLA-Tencor.