 Depending on the complexity of the API for the level where faults are injected, fault injection tests often must be carefully designed to minimize the number of false positives.Even a well designed fault injection test can sometimes produce situations that are impossible in the normal operation of the software.For example, imagine there are two API functions, codice_3 and codice_4, such that alone, each of these functions can possibly fail, but if codice_4 is called and succeeds, a subsequent call to codice_3 is guaranteed to succeed.