You're not going to be able to sell a piece of software based on the idea that it has less bugs. People expect software to be bug-free. When people buy a new version of a product, people expect new features. I mean, history has proven him completely correct - today, vendors provide free updates in their software to fix bugs and sell new versions with more features.
Secondly, you're always going to have bugs. It's inevitable. What's important is that your software, both in terms of design and testing, is resilient enough to avoid major bugs that a large proportion of people will run into. Historically, Microsoft were good at this - there's a reason they were behind "Writing Solid Code". What remains are bugs which are quirks and corner cases, which are generally less important and are harder to test for. Of course, the situation with security is rather different, as certain quirks and corner cases can have serious unintended repercussions.