Estimating the number of components with defects post-release that showed no defects in testing
Components that have defects after release, but not during testing, are very undesirable as they point to 'holes' in the testing process. Either new components were not tested enough, or old ones were broken during enhancements and defects slipped through testing undetected. The latter is particularly pernicious, since customers are less forgiving when existing functionality is no longer working t