Software Defect Reduction Top 10 List

I've just found interesting article on statistics behind defect reduction by Barry Boehm and Victor Basili: here.

According to the article top ten defect reduction list is the following (I'm citing the article):

1. Finding and fixing a software problem
   after delivery is often 100 times more
   expensive than finding and fixing it during
   the requirements and design phase.


2. Current software projects spend about
   40 to 50 percent of their effort on avoidable
   rework.


3. About 80 percent of avoidable rework
   comes from 20 percent of the defects.


4. About 80 percent of the defects come
   from 20 percent of the modules, and
   about half the modules are defect free.


5. About 90 percent of the downtime
   comes from, at most, 10 percent of the
   defects.


6. Peer reviews catch 60 percent of the
   defects.


7. Perspective-based reviews catch 35
   percent more defects than nondirected
   reviews.


8. Disciplined personal practices can
   reduce defect introduction rates by up to
   75 percent.


9. All other things being equal, it costs 50
   percent more per source instruction to
   develop high-dependability software
   products than to develop low-dependability
   software products. However, the
   investment is more than worth it if the
   project involves significant operations
   and maintenance costs.


10. About 40 to 50 percent of user programs
    contain nontrivial defects.