Figure 5: Graphing percentage of defects detected (Y axis) against an organization’s software development maturity level (X axis).
Let’s assume an organization at CMMI level 2, with 1,000 defects detected during functional testing. Figure 5 shows that on average, without QM practices, about 30 percent of the defects are being detected in functional testing (the left, blue bar), and therefore the total number of defects is 3300. However, by applying TM practices, the defect detection rate increases to 58 percent (the right, green bar), therefore detecting 1914 (58 percent of 3,300), or 914 more defects.
As fixing defects during User Acceptance Testing (UAT) is about 7 times more expensive than during Unit/Integration test, and assuming a fix cost of $120 per defect during unit/integration test, fixing 914 defects in UAT is already increasing the cost by over half a million dollars.