> Not just for paranoid maniacs. "Stable" has two meanings: "robust" and "unchanging", and both are highly correlated: software that changes tends to be brittle.
I don't buy that. There are dozens of projects that prove that it's perfectly possible to develop new features while not introducing regressions all the time, such as Apache httpd, Postfix, PostgreSQL and many others.
Robustness is primarily a result of good design, developer competence, care and good development practices, not of age and lack of changes. Sendmail has had much more time to mature than Postfix, yet the latter has had far fewer vulnerabilities. And BIND 8 was so broken that they decided to throw it away and start over, resulting in the much more robust BIND 9.