If it's cold outside and the bike is cold you bring into say 68 degrees, something like a bike will get condensation on it. The bigger the temperature difference the more condensation there is. The faster you warm it up the worse it is. If you need to go outside when there is still condensation on something it will turn to ice if it's cold enough.
If you get condensation in the frame you can't see it. if you get some in the cables it can freeze the cable solid if there was not enough time to dry the bike out.
If you bring the bike inside let it warm up slowly, and let it dry all night long. I've seen frozen cables from this a couple of times. I was deer hunting when it was about 20f, brought the shotgun inside, leaned it against the wall and the water was pouring off the weapon.
Or leave the bike in the cold. maybe a garage, or a shed, and wear the right clothing. I do it all the time.