Yes, everybody with 100% market share can only lose market share, and they will except if they are Microsoft (clinging on to market share with illegal means). Even IE once had 96% market share, does it make it a failure having 40% today? No. It's just like every market where there are two or three big players sharing the pie. I don't say that symbian was the ultimate OS, but you don't ditch #1 for #NaN. And if you finally decide to do it anyway, help the damn transition.

Nokia has many times broken compatibility with old systems successfully. The N9(1-5) were a raging success even if they didn't play the old S60v2 applications. They could easily, if Symbian was really the problem move to meego, as the same toolset (Qt) enables transition to meego. Or even WP, but with a transition path, not "go sell all your software and hardware and come back next year"

And even if Meego "was not ready" we have proof that they moved faster than the WP train which took a year to deploy Mango, with not-so-awesome updates, and they 'll need another year to support NFC and MicroSD things that M*E*O already supports.

Anyway that is out of the current stream of discussion. We are discussing about the WP7 failure today and not the decision to go WP7 last year. And todays' condition is attributed to a million reasons, one being WP7 itself as a system (nobody seems to want one) and many others like bad execution, stupid campaigns, removal of Symbian phones from the shelves (not new models, old ones that cost nothing to be there as an option for the guy that's say... stuck to the past), no HWKB devices (a traditional Nokia strength) etc etc. It is also attributed to the market share Nokia already lost, that will never return due to platform lock on. Had they kept quiet, and ditched Symbian this february, with 3 Lumias ready to ship, they would have much more customers going to the store just asking for the new Nokia.

And finally, why ditch it at all? Make two Lumia Flagships, market the hell out of them, if they sell well, fade Symbian to oblivion, nobody will mourn. When they said the N8 will be the last Symbian N-Series the market didn't crash. When they said symbian is crap, then it did. And if not all goes well and you see people are not loving your new babies, repaint your N8, give it a new processor and a bit of more ram, buy some time until you have something people will love to buy.

EDIT: Bleeding money?? When did that happen?