When we moved into our current home we found that the floor in the garage connected to the house was slippery when a little rain or snow got on it. Like "ball bearings on glare ice" slippery, so we had it coated.
The shed also has a concrete floor, and when my wife asked if I thought we should have that coated as well, I told her, "Hell, no! All of those stains and smells tell the history of this place!"
And I'm doing my best to add some "history" of my own to that floor.