Chapter 5. Cost of Change

Under certain circumstances, the exponential rise in the cost of changing software over time can be flattened. If we can flatten the curve, old assumptions about the best way to develop software no longer hold.

One of the universal assumptions of software engineering is that the cost of changing a program rises exponentially over time. I can remember sitting in a big linoleum-floored classroom as a college junior and seeing the professor draw on the board the curve found in Figure 1.

The cost of change rising exponentially over time

Figure 1. The cost of change rising exponentially over time

"The cost to fix a problem in a piece of software rises exponentially over time. ...

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