"Edwin Pawlowski" wrote:

Probably the same reason many of us have. We use the garage as a work shop
and like it to be a bit warmer in the winter. Do you find that odd for some
reason?

And has been pointed out by multiple people, insulating a garage door in an
uninsulated garage is going to do bupkis for keeping it warmer, especially if
there is no living space above or around the garage.

Sealing any airgaps around the door may help keep things less drafty, although
you would need to be mindful of any open flame devices in the garage that need
makeup air (ie furnace or water heater). Vents for those should never be
blocked.