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Nov 10, 2002
Preemptive costs vs. Costs of failure
When should you not undertake preemptive measures to preventing potential failure and fixing the cause? In probability terms: When the expected probability of a failure multiplied with the sum of the cost of fixing the failure and the cost of the failure itself (with customers, e.g.) is lower than the cost of testing plus the expected probability of failure multiplied with the cost of fixing the failure. Or for a better explanation, read Joel Spolky's piece.
Of course, this calculational model does not only serve you well on load testing, but basically on all other issues where you have to weigh preemptive costs vs. cost of failures. That's nothing new, but always worth being reiterated. In the hectic of daily life, it gets forgotten too often, especially by people who put orders into an IT department (internal customers) as well as the people that take on these orders and have to prioritize them (usually also the IT department).
Posted by Stefan Smalla on Nov 10, 2002 at 12:46 | Permalink