More defects are found by the formal method than the informal method. Significantly fewer defects remain in the software for detection during the test stage following the formal methodology. A significant labor savings thus occurs with the formal methodology. This effect is also modeled in Table 5. Another benefit of inspections is that product developers and designers attend inspections of their products.
Developers learn that certain types of errors tend to occur repeatedly in their products.
As a result those types of errors do not appear again and the products become more error free at the time of inspection.