Are we talking about HW only?
Cyanogenmod. And don't tell me they had Android. Mer and Meego where there for a while too
Pebble
NextThing
Oculus Rift
A lot of 3D printers companies(their own SW and HW is more complicated)
puzzlephone is boosting

And please do not tell me, that Jolla did more. Yes they made mobile OS, but they had Mer and meego already, those people worked on maemo before (they used it in PR, so why can't I point that out). They provided updates, but basically long changelogs did not include a lot of new features. There are a lot of bugs that still are there from the begining. And if they decided to throw all the money in that and tried to conquer whole world(in their case it was EU + some more countries), but not proceed slower but in great acceleration — their fault. I see it as someone who know to run sprints and trying to use same method to run marathon. The problem that he will loose all his strength at very first kilometers.
They had enough time and money and if they decided to use not wisely and ask for more and more, then all your "they have no backing and they are small" is an excuse. Because if you know that, they should know it better and do not try to jump over own hands. They had connections, they had first investments, they had community behind, but they blew it all away. Their management lost mind in fame at the beginning and ran away from boat