It's all subjective. I thought the weather in CO sucked, myself. Sure it's nice in the summer, but sucked in the winter. Cost of living and quality of life, for me, was terrible as well. Sure, it's beautiful. But I got tired of not being able to leave my home on weekends for what should have been a 15 minute drive to Conifer because of traffic that made it an hour and a half drive. I got tired of paying what I considered to be exorbitant taxes and fees for the privilege of driving a newer car. Politics was a factor for us...but it was pretty far down the list. Now we live in a place that's just as pretty, FAR less congested, has better weather and the cost of living is FAR less than Colorado. I can't think of a single way CO was better than here. Not one.
And, BTW, I'm not a CO native but moved there in 75...so, pretty close.