The present invention enables a method for following the state of a call and generating defects as function of call completion success as opposed to discrete events that happen at individual network elements during the call. In one embodiment, the invention uses Call Detail Records (CDR) to analyze the end-to-end completion status to measure per call basis defects instead of using defect codes generated by network elements on a per equipment basis. CDR is data associated with a telephone call, including the calling and the called numbers, the date and timestamp, the duration, the call setup delay, and the final handling code of the telephone call.