From M.Costales in G+ :

This is gold! You have to read those posts!
Why and how +Ubuntu #phone & +Firefox OS died:

http://www.lieberbiber.de/2017/06/20/my-ubuntu-for-mobile-devices-post-mortem/

&

https://medium.com/@bfrancis/the-story-of-firefox-os-cb5bf796e8fb#.pe1bgn42v