Momentum. The OS was shaping up nicely. There was the promise of WP8.1 GDR2 and W10M on the horizon, Microsoft finally seemed to have gotten it together. Plus, recent launch of flagship 930 worldwide and the midrangers 730 and 830.
Now ? Crap low ends, apps universally better on competition, the OS unstable, buggy, slow, no handsets released in over a year (again), except for the great, albeit still generally uninteresting 640/XL.
Today it's bad decision over bad decision.