With the moves that Elop has made since his introduction as the Nokia CEO, I hardly see how he could survive another failure. If the Lumia line once again fails to catch on, he's gone. The shareholders won't stand for anymore stagnation. When people go into their carriers stores, they are walking out with an iPhone or a Galaxy SIII for the most part. The Lumia lineup is pretty intriguing, but 1. having it as an AT&T exclusive was a bad idea. 2. even though they have Microsofts backing, their marketing dollars have pretty much gone to waste. iPhone, Galaxy, Droid, they're all household names. The Lumia just doesn't have the recognition right now. It was a shortsighted decision for Nokia to align itself solely with a fledgling OS. Not saying Android was the way out of the dire straits Nokia was in, but they could have at least offered devices from both OS's. Samsung does it, HTC does it, and a few other OEMs do it. There's nothing wrong with playing both sides of the smartphone fence. The Lumia Nexus could have been launching alongside the Lumia 920, and likely would have been a success. Pride got in the way of Elop forming a partnership with Google alongside his Windows Phone selection, and it may cost him in the long run.
Im saying that Nokia and especially Stephen Elop did not have the choice to go with Android and Windows Phone at the same time, it was far too risky for Nokia and Nokia was late from this game because of Olli-Pekka Kallasvuo, Anssi Vanjoki, Jorma Ollila and many other old leaders of Nokia.
So why was Android out of the question? It was because Nokia was afraid of the patent wars. Now hold your horses and let me explain what I think. Looking through the Economics of Nokia we find out that when Stephen Elop took over in Nokia, Nokias sales were going down fast, the Symbian products did not sell enough and Elop saw this, he knew that there was something that needed to be done really fast.
They propably looked through various of options which propably were:
Develop Symbian and MeeGo and sell them there was a major downside in both of these products, in Symbian the problem was that it was just terrible compared to Android, it had no real advantage over Android.
The MeeGo was good and it down right had everything needed to compete with Android exept Apps and LTE (WHAT!?!??!?!), yep LTE was missing and thats because it was developed with Intel and it supported Intels chipset which did not support LTE.
Jollas version of MeeGo which they are announcing sometime later this year will not be exactly same MeeGo what we saw in the N9, infact they have stated that it is completely different platform even though sharing a lot from MeeGo and thus also the name change to Sailfish.
So the consumers didnt want the Symbian and MeeGo could not offer them a future, let alone an ecosystem. Decision was made to ditch Symbian and MeeGo.
Second option was propably the Android development: So Nokia saw that they could get a platform and a working ecosystem from Google, but they also knew that it would take time and they would need to fight patent wars consistantly with Apple and Microsoft and they would have dosens of competitors who allready have products with the same platform not to mention that they would still have to do something to differentiate themselves from the others. And Google did not offer them any exclusives. So even though it would have been possible to work with Android but it also had its downsides.
Third option do both: Android and Windows Phone: This would have put Nokia in the same position with Samsung and HTC and they wouldnt have anything exclusive from Google nor Microsoft, they would have been just another OEM.
4th option, go with Microsoft: Good things, get 1 billion dollars each year from Microsoft and get your maps to be the primary maps used in WP and W8. Get exclusive deals with third party app producers so differentiating with other OEMs.
The downside with this was of course the fact that Windows Phone does not have a huge marketshare like Android so it would take time and effort to create that marketshare.
Anyway the 4th option was the one they took, one reason was also propably because they taught that they could make theyr organisation more agile and that would lead Nokia to be able to make better products in less time and give better customer support.
I know this is a really raw version but I really cant be bothered to write 10 pages of analysing the whole situation.