How do you prioritize testing? You can't do everything. So you should spend your time on tests that have the most bang for your buck. Risk based testing attempts to solve this problem.
There are two dimensions to risk. One is the technical dimension. This is where the developers use new technology. Another dimension is the business one. Where in the apps is there a high cost to the operations if there is failure?
You can use the two risk dimensions to prioritize testing. The areas that involve both a technical and business risk need the most testing resources. Other areas that have either one or the other dimensions of risk should be tested next. The low risk areas can be saved for last or skipped entirely. The result is that you spent your time wisely.
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