Bolts Romano :
Many people do not realize Nokia already losing in all front prior Elop.
Without Elop or Microsoft, Nokia already in the same faith as Ericsson.
True, but the decision to continue to neglect Android entirely in favor of Windows likely accelerated the process. Elop's former experience with (and likely bias in favor of) Microsoft was most certainly a major determining factor in this decision.
I'm not saying using Windows phone was a horrible idea as it helped differentiate Nokia from others, but there was no reason why Nokia could not have also released Android phones at the same time to appeal to a much wider audience.
Elop is also responsible for the terrible product marketing of the Lumia line. The alphanumeric naming scheme was convoluted and confusing in a market that favors simplicity. There was no opportunity for an individual flagship model to achieve any sort of recognition because of so many variants. Steve Ballmer himself admitted as much when MS took over.
My Fiance has a Lumia 928 and always tells people she has "The Windows Phone." I'm not sure she even knows it's called the Lumia or 928 and frankly doesn't care.
Elop hasn't shown he has any sort of outstanding insight into market trends or any sort of innovative ideology up his sleeve. He is most definitely the wrong person to lead Microsoft unless you want more misdirection.