I had a Nokia 920, then a 1520, both running Win Phone 8. For the state of things at the time, they were promising and, honestly, great. More stable than Android at the time (that's anecdotal, but my wife had an Android phone and it seemed to have more issues than my phone did), and was far more customizable than an unrooted iPhone (LiveTiles really is a great idea, IMO). Sadly, the combined hardware-software improvement that came in the move from Phone 7 to Phone 8 was a one-time event, apparently.
As I waited in anticipation for what I hoped would be some ground-breaking software innovations in 10 and fun/useful hardware features to give them life, I was at first in denial, then dismayed, next angry, and finally in acceptance (the ecosystem is diseased, after all) that MS entirely dropped the ball and screwed it all up. I'm no fanboy, but I really did hope for a strong third alternative. Once it was clear that my 1520 wasn't going to physically survive the last time I dropped it, I moved to a Nexus 6P, and I've been very pleased with the experience six months in.
So long, MS - it's your fault that you lost someone who was willing to be a loyal customer if you had shown some competence in the mobile area. I work in IT for a hospital, and can report there were four other people in the department who owned one a year ago, and don't today, so I'm willing to lay odds that you've lost not one, but five. I suspect that 2 million and change will continue to slip downward.