Should garage floors always be made with a slope for water?

I’m accustomed to Florida residential, and garages are built so water will drain out of the garage. My husband and I are looking at a commercial garage in another state, and there is water sitting in one spot in the middle of the garage. The salesperson said he left the door open during a rain storm. I figure that’s a low spot in the garage. He said in commercial they don’t have the rules about water draining out, that the floor should be flat, similar to a house floor.

I’m thinking about asking the county, but interested in what the collective has to say.