At 17 degrees and below, mine would never start without a battery jump.
I remember reading an article about a guy who had a old Triumph in Minnesota. He set his alarm at 2:30 am every morning so would get up and start the car going down on a hill, drive it a little bit to warm it up enough so it would start at 8:00. Then he went back to bed. One day he raised the trunk lid to fix a flat and a semi went by, and the wind tore off the trunk lid. He still had fond memories of the car.