Originally, the reason Nokia nurtured so many third party companies to develop Maemo/MeeGo was the expectation that by doing that, they would bootstrap the whole ecosystem of companies around the platform. When I first got involved I thought that a very smart strategy, and I still am convinced it would have worked. Other parts of Nokia's strategy were pretty brilliant, too. But then... Other parts again were so bad.
I remember the sudden burst of anger in Ruoholahti when the N8 was released with Symbian on it. Nokia people I talked too were genuinely surprised it wasn't a Maemo device.