While tight schedules often rob us of the time needed for adequate testing, time is not always the sole culprit. We often lack an adequate understanding of what testing involves. Common Problems Products have not been engineered for testability. Requirements to test against are often either ambiguous or missing. Planned testing lacks appropriate focus.
Test preparation falls short of the mark.
Review of test procedures may be done cursorily or not at all. A disciplined method, e.g., failure mode effects analysis, is not used to identify probable error-causing inputs as test data. Test resources are inadequate. Too little time is allotted for testing. Test beds do not provide the CPU cycles needed to execute the desired number of test cases.