6.2 Root Cause Analysis
Root-cause analysis is the process of finding the activity or process
which causes the defects and find out ways of eliminating or
reducing the effect of that by providing remedial measures.
The root cause analysis of a defect is driven by two key principles:
Reducing the defects to improve the quality: The analysis
should lead to implementing changes in processes that help
prevent defects in the formation stage itself and ensure their
early detection in case it is re-occurring.
Utilizing local and third party expertise: The people who
really understand what went wrong should be present to
analyze processes prevalent in that organization along with
third party experts. A healthy debate ensures all possibilities
are reviewed, analyzed and the best possible actions are
arrived by consensus [5].
With these guidelines, defects are analyzed to determine their
origins. A collection of such causes will help in doing the root
cause analysis. One of the tools used to facilitate root cause
analysis is a simple graphical technique called cause-and-effect
diagram/ fishbone diagram which is drawn for sorting and relating
factors that contribute to a given situation. For the projects
mentioned in Table 1, the major causes making software defect to
happen are represented using a cause-and-effect diagram, as shown
in Figure 6.