In maintenance, the regression tests ought to be performed when the potential loss that could occur because they affect a party without changes is very high. The determination of whether to perform regression testing ought to be based on the importance of the loss that could occur due to requests the test correctly. Regression testing is a new analysis technique segments without application changes. Usually it is re-run the tests that have been historically in the past issued to make definite that the same results can be achieved at present as were achieved when the segment was tested last. While the method is simple in that test transactions have been prepared & the results known, unless the method is automated, can be a very time consuming & tedious operation. It is also one in which the cost / benefit ought to be carefully evaluated or most of the efforts can be inverted with the maximum investment return.