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.

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.