Why do some hate WP7 so badly?

I have an iPad, the Kindle Fire running Cyanogen mod 7 and the HTC Desire. When I first saw the WP phones last year, I thought my god what an ugly UI. Then, when Nokia came out with the N9, I thought it was the most beautiful thing ever, and desperately wanted one. That turned into renewed curiosity about WP when the Lumia 800 was launched, and now I have to say I thoroughly love WP. It is way ahead of any Android phone I've ever tried (and I've tried quite a few) in usability and fluidity, and very refreshing in that it's not just another "tons-of-icons-on-a-picture-background" UI.

Which brings me to my question: why is there so much hate against WP from so many people? Are the haters mainly tweens and teens with too much hormones in their veins or is it a result from being too attached to something that should be very un-emotional, e.g. which OS runs on your phone?

Rational thinking should welcome a new player in the market, as that will increase competition, thus driving prices down and availability and quality up. Why is this not the case with WP?