Here are a couple of details about programming at Google. First, every commit requires a code review. Secondly, in addition to writing your own tests and testing tools, there is a separate set of developers that do nothing but write testing infrastructure, ensuring that it's as easy as possible to test everything as it's written.

Bugs still happen, of course, but they're going to be of the more obscure variety. My chromium 14.0.835.202 has never crashed. Always good to get a backtrace and read the code nearby, and if nothing makes sense, run memtest86.