Boris Beizer quotes:

A design remedy that prevents bugs is always preferable to a test method that discovers them.

More than the act of testing, the act of designing tests is one of the best bug preventers known.

A test that reveals a bug has succeeded, not failed.

Software never was perfect and won't get perfect. But is that a license to create garbage? The missing ingredient is our reluctance to quantify quality.

Second law: The complexity barrier. Software complexity (and therefore that of bugs) grows to the limits of our ability to manage that complexity.

Bugs lurk in corners and congregate at boundaries.

If you can't test it, don't build it. If you don't test it, rip it out.

A good threat is worth a thousand tests.

One of the saddest sights to me has always been a human at a keyboard doing something by hand that could be automated. It's sad but hilarious.

If the objective of testing were to prove that a program is free of bugs, then not only would testing be practically impossible, but it would also be theoretically impossible.

First law: The pesticide paradox. Every method you use to prevent or find bugs leaves a residue of subtler bugs against which those methods are ineffective.

Extra features were once considered desirable. We now recognize that 'free' features are rarely free. Any increase in generality that does not contribute to reliability, modularity, maintainability, and robustness should be suspected.