I may be wrong, however when Nokia entered into agreements with Microsoft it seems to me they had the expectation they would be their flagship phone provider. And yet when Windows 8 phones were made available Nokia was still stuck on the older platform for their most current phones. Exclusivity would have made Nokia the main source for Windows phones. The other companies such as LG and Samsung used both Windows phones and Android phones so they never had this issue.
I think the biggest problem is that they charge for their operating system, which is fine for the Lumia 920, but isn't practical on low end phones where Nokia actually still has some market share. Or at least not practical at the rates Nokia is obliged to pay.
Are you saying that the charges made Nokia impossible to succeed? What about the patent fees android OEMs have to pay?
I don't know if I would say impossible to succeed. But by demanding full price for the OS, even on low end phones, it meant that Nokia rolled out far fewer windows phones. I think that was bad for Microsoft and Nokia, and indicative of old school desktop thinking on Microsoft's part.