When I first read this
“Program testing can be used to show the presence of bugs, but never to show their absence!”
I was absolutely fascinated how with only a unique phrase we can clearly express what we are unable to do with several paragraphs, conversations and e-mails.
I have been using database software for more than 8 years, of which the last 3 years has been spent collaborating with the Quality Assurance (QA) team. If I was asked what best is to do to bring software from test to the production environment with less bugs, my answer would be summarized in one phrase: through doubt on your tests
Being in doubt will bring you to ask yourself more and more questions generating uncertainty on what you have implemented causing you to review your code and to test again.
As far as program testing aims to show the presence of bugs and not their absence then doubt will certainly increase the number of bugs we will discover much earlier in development process reducing the number of incidents in the production environment where is it not easy to intervene.
Hence, do you think that doubt is a good or an inadequate skill?
Mohamed Houri’s Oracle Notes 