Creating automated tests can be very difficult, especially when the code has gotten long in the tooth and was not created with automated tests to begin with. Many product development teams don’t invest in automated tests. They think they cannot afford them. They think their product is different and can’t be manually tested. This thinking is flawed.
Back in the products younger days, manual test was not too time consuming. But slowly that changed. The system grows, the manual test effort grows. Eventually, it seems that no amount of manual test effort finds all the problems.
In this article I show a simple model that illustrates why manual test is unsustainable and that a sustainable software product development effort must include considerable test automation.