"...this is a properly tested project. We even have 85% test coverage!" told John, a coder, proudly to his colleague, Mike, whom he just met next to the coffee machine after not seeing each other for a while. Mike was not really satisfied and asked: "And what about the remaining 15%?"
John stated that the part of the code in question is not really important, partially not even used anymore. And anyway, it was tested manually. And, of course, they keep adding new and new classes to the Sonar-Exclude in order to hide code, which can not be tested, from SonarQube.