1. Mahindra Satyam Confidential Quality Management System Software Defect Prevention

2. Mahindra Satyam ConfidentialIntroduction Defect Prevention is a level 5 PA (Causal Analysis and Resolution) as per SEI CMMi The purpose of defect prevention is : –Identify causes for the defects –Implement actions that can prevent these defects

3. Mahindra Satyam Confidential Principles of defect analysis and prevention  Learn from mistakes  Understand why problems occur  Determine priorities and focus on problems that really matter  Use an evolutionary approach; tackle one problem at a time  Use feedback to improve the prevention and detection of defects  Don’t use defect analysis to assess the performance of individuals  Defect prevention takes time and commitment  80 percent of the problems can be traced to 20 percent of all possible causes

4. Mahindra Satyam Confidential Principles of defect analysis and prevention  Programmers should evaluate their own errors  Causal analysis should be a part of the process. This leads to :  Spreading the work  Involvement of appropriate people  Creates environment for emphasizing prevention of errors as a daily activity  Feedback should be a part of the process

5. Mahindra Satyam ConfidentialProcess KICKOFF MEETING CAUSAL ANALYSIS REVIEW MEETING ACTION TEAM FEEDBACK INSPECTION DATA + DEFECTS SOLUTION RECOMMENDATION ACTION SYSTEM ENTRY TASK VALIDATION INSPECTION REWORK FOLLOWUP EXIT FEEDBACKFEEDBACK e.g error list

6. Mahindra Satyam Confidential Role of PL/PM Planning defect prevention activities Ensuring that defect data is available Participate in causal analysis meeting Track progress of defect prevention action items Evaluate effectiveness of defect preventive actions

7. Mahindra Satyam Confidential Role of QR Provide assistance in causal analysis Review defect prevention plan Coordinate action team meeting Monitor project process for defect prevention

8. Mahindra Satyam Confidential Defect Prevention Activities Causal Analysis Defect prevention action plan preparation and tracking Evaluation of effectiveness of defect prevention actions –Improvements of checklists –Training Defect prevention Planning

9. Mahindra Satyam Confidential Defect Prevention Plan Identification of Causal Analysis Team Schedule and frequency of causal analysis meeting Plans for defect prevention action Frequency and criteria for effective defect prevention actions Frequency and criteria for effectiveness evaluation of DP

10. Mahindra Satyam Confidential Defect Prevention Activities Defect prevention action plan preparation and tracking Evaluation of effectiveness of defect prevention actions –Improvements of checklists –Training Causal Analysis Defect prevention Planning

11. Mahindra Satyam Confidential Causal Analysis More information to be obtained about each cause The phase of the project when defect was injected If the cause was due to : –Non compliance to QMS - the reasons should be determined –Gap in process - the process aspects should be reviewed

12. Mahindra Satyam Confidential Selection of Defects for Causal Analysis Meetings Defects attributed to most prevalent defect type All customer related defects All high and medium severity defects Defects which require maximum rework

13. Mahindra Satyam Confidential Causal Analysis Meetings Objectives of the meeting should be : Analyze defects Evaluate results against team goals General Process Improvements

14. Mahindra Satyam Confidential Causal Analysis Meetings For long duration projects : Causal Analysis meetings should be held when data is available for at least 25 defects. For short duration projects : Causal Analysis meetings should be held at the end of each phase For maintenance projects : Causal Analysis meetings should be held monthly.

15. Mahindra Satyam Confidential Causal Analysis Meetings PL will identify the scope of meeting Causal analysis team shall include PL and concerned ML/TM The team will verify the defect analysis and also discuss actions required for preventing similar defects from recurring. The action items derived from the meeting shall be disseminated to the team members

16. Mahindra Satyam Confidential Causal Analysis Tools Causal Analysis Tools are: –Pareto Charts –Fishbone Diagrams etc.

17. Mahindra Satyam Confidential Causal Analysis-Consolidating and numerating defects Defect TypeNo of defectsCumulative Documentation 45 Logic 3378 Computation 583 Standards 487 Configuration 390 Interface 292 Others 294 System 296 User Interface 197 Data 097

18. Mahindra Satyam Confidential Causal Analysis - Pareto analysis

19. Mahindra Satyam Confidential Causal Analysis- Preventive Actions

20. Mahindra Satyam Confidential Cause & Effect Diagram - An Example Documentation Defects IndividualEnvironment Work PlaceGroup / Project Health Lack of Experience Lack of Motivation Assumption Attitude Over Confidence Least Imp Carelessness Self Review Not Done Monotonous Work Volume & fatigue Office Relationship Motivation Time Pressure External Home

21. Mahindra Satyam Confidential Role of Causal Analysis Team Perform defect analysis to identify the causes of defect Identify preventive action to prevent the recurrence of these defects

22. Mahindra Satyam Confidential Defect Prevention Activities Evaluation of effectiveness of defect prevention action Causal Analysis Defect prevention Planning Defect prevention action planning and tracking

23. Mahindra Satyam Confidential DP Action Planning and Tracking

24. Mahindra Satyam Confidential Action Items

25. Mahindra Satyam Confidential Defect Prevention Activities Evaluation of effectiveness of defect prevention actions Causal Analysis Defect prevention Planning Defect prevention action planning and tracking

26. Mahindra Satyam Confidential Evaluation of the effectiveness of defect prevention actions Reduction in total number of defects Reduction in number of defects attributed to the cause for which preventive action has been taken. Reduction in rework effort Reduction in review/testing effort

27. Mahindra Satyam Confidential Repository is collection of output of defect prevention actions. Typical contents are –Process Changes –Common Error Lists –Checklists / Guidelines –Templates –Technical Write-ups –Tools –Any other output of a defect prevention action Defect Prevention - Repository

28. Mahindra Satyam Confidential Repository - Project / SBU Level Collection of output of defect prevention actions of individual projects in common, shared area

29. Mahindra Satyam Confidential Cost and Benefits of DP Major Costs –Cost of conducting several meetings –Cost of gathering data –Cost of tracking, reporting and dissemination of information –Cost of Training Trade off –Less effort on testing and bug fixing (cost of bug fixing increases exponentially with time) –As the time for bug fixing becomes less, the same can be used for process improvement/ improving functionality leading to overall customer satisfaction –Improved documentation –More efficient and productive organization

30. Mahindra Satyam Confidential Cost and Benefits of DP Contd... One work request had many errors related to error messages These were analyzed and preventive actions implemented in the next work request Customer Feedback -”The delivery of this work request is fine. None of the errors of previous work request are present in this delivery” - Customer Satisfaction

31. Mahindra Satyam ConfidentialConclusions Error detected at an early stage are easy to analyze, correct and is less expensive Cost of finding and fixing errors increases exponentially at a later stage Studies show that if defects can be ironed out at development stage by using suitable DP techniques 90% of the total defects can be reduced DP results in improvement not only at project level but also at organization level resulting in increasing customer satisfaction. Without analyzing the statistics and defects the fine tuning of development process is not possible

32. Mahindra Satyam Confidential TAP3 CONVERSION FOR MOBILE-X Case Study

33. Mahindra Satyam Confidential DEFECT CONSOLIDATION TOTAL DEFECTS : 139 By Severity High : 74 Medium : 18 LOW : 47 By Type Documentation : 45 Standards : 34 Computation : 5

34. Mahindra Satyam Confidential DEFECT CLASSIFICATION BY SEVERITY

35. Mahindra Satyam Confidential DEFECTS BY PHASE OF ORIGIN

36. Mahindra Satyam Confidential DEFECTS BY TYPE

37. Mahindra Satyam Confidential Analysis of Checking Error TAP3 is a New Standard First Project of This Type Lack of clarity in the Standard Standards Error Coding Standards not Properly followed

38. Mahindra Satyam Confidential The purpose of defect prediction model is : Project the number of defect Monitor and manage the quality of the application when it is under development Mahindra Satyam’s Defect Prediction Model: Defect Prediction Model