i'm glad Mozilla had the foresight to abandon this project right before it became a profitable enterprise.
Their timing was poor too. The market was saturated with alternative OSes back then and not enough PR oxygen to go around.
- Nokia Meego OS
- Windows Phone
- Blackberry Playbook OS/BB10 OS
- Sailfish OS (ex-Nokia people)
- Ubuntu Touch OS - WebOS
What Mozilla built was an OS that could run on very basic hardware (eg: what an OEM can build for $5 to $10) and be more usable than the alternatives out there that were even more expensive.
A price war led by Mozilla was never going to pan out without buy-in from the OEMs and cell carriers, but after Mozilla ditched the project, Qualcomm seems to have decided KaiOS is the only reasonable thing for basic phones to run, and Google is funding it just enough to encourage integration of some Google services.
Does it help to keep the web open? Does it bring revenues to justify the risk and loss of focus ?
For starters, they targeted feature phones instead of Smartphones
KaiOS had the benefit of hindsight to see where Mozilla fell over, put in mitigations, and then shift focus to non-touchscreen devices to lower costs even further.
A lot of their stack is still open source under the MPLv2, however there are rumours that Google is 'encouraging' KaiOS to shift their rendering engine over to Blink. Whether this happens or not remains to be seen.
Mozilla ditched Firefox OS & Thunderbird over the huge amount of work that would need to be redone to move to newer Gecko (as Servo components were ported over and swapped in via Project Quantum), but that would likely be less work than getting Blink to be responsive with minuscule amounts of RAM, then go app by app and optimize the crap out of it (which Mozilla had dozens to hundreds of devs doing for Firefox OS while they were developing it).
Mozilla really just got caught in between being an OSS organization and working with proprietary phone companies, carriers, baseband developers, etc. We were used to working transparently on wiki, Github and IRC, and suddenly had NDAs and confidential code that partners insisted on. There was a large culture clash, and the effort both took a bunch of momentum from the browser side and ended up putting unique technical constraints on Gecko and the Firefox Browser, both in terms of necessary functionality and on the development cycle.
That last could be a killer because you couldn't do anything quickly as everything had to be tested at length for interoperability, etc. FxOS was usually pinned to something older than the browser development (consider the security bug implications there) for extended periods of time, and teams had to shuttle fixes back and forth. Given that some of the changes were basically hacks to get the phone going and had no benefit to the browser, I'm sure that caused a lot of friction.
Partners also wanted to see formal processes guaranteeing their stake, and that was at odds with the more "steer don't plan" way Mozilla tended to run. The people that were brought in that were more familiar with formal process and could make partners happy weren't as familiar with Mozilla's community or culture, and that also churned things a bit.
Basically, it was a perfect storm of issues to deal with--Brendan leaving was just one of them, and possibly the least important. Morale wasn't awesome, and the window of opportunity for a new smartphone OS was closing--if it was even open in the first place.
While there was some talk around shifting to feature phones as a focus/market gap (basically what Kai has done), it was very late in the game. After a point, I think a decision was simply made to cut bait and get back behind the browser again. Quantum was the (IMO very good) result of that focus.
Honestly, Mozilla did as well as I'd expect any organization of its type and size--which is not as well as I'd expect a greenfield organization tightly concentrated on the goal to do. KaiOS is that latter thing.
Firefox OS, neé B2G, was a skunkworks project for sure, which needed shaver and me as exec sponsors to avoid being killed in the cradle.
KaiOS's success could be read as us being too early (but we always thought we were late, starting in 2011); or as Mozilla not sticking it out and working on the low end to make deals such as the JioPhone one and others which I think were under way with Verizon. Whatever the case, KaiOS pulled off the vision and used code and engineers from FirefoxOS, which counts as a win for the concept.
Edit: so if the "window was closing", did it re-open? I think rather the window was always open, some variable amount, and awaited Reliance Jio's amazing growth via free-for-N-months 4G data. Android never fit in the low end, so the window was always there at some width of openness.
The main reason that Firefox OS was shut down was that management wanted to focus on western markets and desktop, which was and is the only revenue driver. I left since I didn't see any growth or opportunity or interesting problems to solve in that Venn diagram.
I was wondering why it failed when it had so much going for it. Tragic.
It makes you wonder the secrets that Google withhold...
However there was an open source implementation (MozRil) that worked well enough.
FirefoxOS failed commercially because we could not get on board the content partner(s) that make or break a mass market Mobile OS.
When I left, Andreas was already lined up as CTO and Li Gong was still heavily involved in FirefoxOS -- I'd appointed Li COO but that got walked back, I think. Li stuck around for a year but left a year later (https://techcrunch.com/2015/04/15/mozilla-restructure/) to do Acadine. Andreas left in June of that year (2015). You'd have to ask them for details, if they are able to comment at all.