Let me tell you something: there's nothing that QA has ever missed that developers didn't miss first.
Blaming testers for not discovering flaws that they did not create while simultaneously believing that we don't have to check our own work while is it fresh in our own minds is dishonest. There's no defect ever found by a tester that wasn't first designed and implemented by a developer.
Software is a production industry that generally still believes that the people who make things and the people who prove that those things are right should be different people doing two parts of a single job at different times.
Part of a tester's job is to cross check the work that has already been checked by the workers who create the software and who have the best, timeliest knowledge of it. When a tester isn't cross-checking, he's analyzing and doing exploratory work - looking for possible gaps in developers' thinking, understanding, and observation. When a developer's responsibility to deliver repeatably-checked work is passed over to a tester, neither is effective.
It's less of a tester's job to check that a developers' code is right, but that their tests are right, or at least that the result of the development so far is right - which includes tests that have been written before final inspection. That work doesn't start after the code has been written, it's starts before, as they work together to ensure that by the time the product and the tests make it to the final inspection, that all the ducks are already in a row, leaving the tester with the space to continue to question exactly what it means for the software to be right, and how to perform final inspections that hold up their part of the shared responsibility for intentional quality and productivity.
Final inspection is the last place that you want to find game-changing flaws and problems. It's the last place you should find them. It happens, but it should be the exception to how development is done, including testing, and the exception to how you treat final inspection.
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