Managing software reliability and support costs

There are probably 30 to 50 defects per 1000 lines of source code injected into the code at creation. The bulk of the software development process is aimed at removing these defects. The average 1-3 defects that reach the field are orders of magnitude more expensive to repair than they would have been had they been removed early in the development. A major key to managing life-cycle cost comes from reducing these latent defects that escape development initiatives and are shipped to the field. The major cause of these field-detected defects is failure to capture all the requirements correctly. Several initiatives described in this paper will aid in assuring early in the program that the requirements are correct. They are the design of experiments, failure mode and effect analysis, defect prevention process and change management