Colorado was taken with the hopes of splintering the Big 12. It was a done deal but they could not any longer employed. When they found out the Texas and Oklahoma would no longer be coming they panicked and grabbed whoever they could get. I looked around and saw little brother utah jumping up and down waving his hand and that's how they got in. Nobody went out searching out utah.
Ultimately BYU is a primary target of expansion utah was a desperation fill in.