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
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.