OS development is not the same thing nor are many other categories. There are too many other things at play. This isn't a hard and fast rule that's applicable to everything.
Mapping is different in the sense that it's primary usefulness comes from being accurate and constantly updated. The best way to do this is from crowd-sourced data. As good as Google Maps is, it still has a hard time keeping current.
I mention Webkit in the same post because one of the most fundamental features of any browser is for a site to be rendered correctly. We've seen the worst of this before with IE and ActiveX
Mapping is different in the sense that it's primary usefulness comes from being accurate and constantly updated. The best way to do this is from crowd-sourced data. As good as Google Maps is, it still has a hard time keeping current.
I mention Webkit in the same post because one of the most fundamental features of any browser is for a site to be rendered correctly. We've seen the worst of this before with IE and ActiveX