Actually, it seemed to me very early on that Nokia's Maemo work was considered experimental lab stuff that was worth pursuing but never truly expected to become Nokia's bread and butter. Once the touch-based revolution started with iPhone and Android, it looks like they scrambled to find something and Maemo was the only "viable" route. Unfortunately, Maemo wasn't rooted in a "we're going to conquer the world" philosophy and $$$ backing. And to add insult to injury, once they discovered that Maemo was about their only card, they decided to merge it with Intel's Moblin without ever engaging the Maemo community about it.
I don't think this is a development philosophy issue as much as it's a lack of market understanding, a failed go-to-market strategy and a breach of trust with an established community. Then again, I might be completely beside the track.