As an owner of both the Kindle Fire (1st gen) and the Nook HD, I can tell why Kindle won and Nook failed. People like Amazon better than Barnes & Noble. Amazon had a head start as a result. Amazon tied it’s popular Amazon Prime service into the Kindle. CEO Jeff BEARS communicated energy and persistence. Barnes & Noble treated the Nook as an obligation. No energy or enthusiasm.
Predictably, developers stayed away. Thus began a death spiral. Too bad, Nook is great hardware. I would have bought another one in a heartbeat.