Rework Requirement Changes in Software Maintenance

The rework cost of a requirement change is high. Requirements changes, which relate to hidden catastrophic failures, can cost many thousands of dollars to fix. An exploratory study on software maintenance records demonstrates that specific change characteristics in corrective change and functional change are shown to have an effect on rework. In pursuing a deep understanding of the effects, we found that unexpected errors and poor understanding of errors trigger higher rework effort. This correlates to 1) weak characteristics and attributes found in coding, 2) the lack of user involvement, 3) unavailability of user documentation, and 4) the lack of motivation and confidence in software maintainers (excluding functional change) to contribute to an increase in rework effort for software maintainers. As such, the author of this paper propose ways to improve the situation by introducing new criteria in change request forms and developing a framework to be used for eliminating rework problems. The understanding of effort rework effects of corrective and functional changes can help software practitioners to be aware that estimation error can be prevented.