'...At some point, of course, the number of “bugs we’ll ship with” will hit 100%, unless we manage to produce the first piece of bug free software I’ve ever worked with, but even with such numerical truisms aside, the picture here isn’t as simple as it seems. “Bug” in our world — as with every software shop I’ve ever worked, to be honest — includes desired feature improvements, optimizations, basically everything in the gap between “how the software is” and “how someone would like the software to be”. Because of history and some tool limitations, and because we now have a larger set of people triaging blocker nominations than we ever have before, the “blocking” flag doesn’t always strictly mean “we would not ship Firefox 3 if this specific bug isn’t fixed”. It can also mean “we should look at this in more detail before we ship” or “we’d like to focus developers on this set of bugs” or “don’t forget to do something (release note, document workaround, reach out to site authors, etc.) here before we ship”...'