Thats a good point.
Wood floors and concrete have a 0 cleanliness modifier but are alot easier and faster to place down. Which makes them a valid option to place early game. If you just want to quikly place a floor to remove dirt thats a good option as well. If you then later want something more suited you could always replace the floor at a later date to get a bonus to that cleanliness.
If all that is happening in your kitchen is your cooks moving back and forth with material to cook, it shouldnt get dirty very fast honestly.
Wood floors and concrete have a 0 cleanliness modifier but are alot easier and faster to place down. Which makes them a valid option to place early game. If you just want to quikly place a floor to remove dirt thats a good option as well. If you then later want something more suited you could always replace the floor at a later date to get a bonus to that cleanliness.
If all that is happening in your kitchen is your cooks moving back and forth with material to cook, it shouldnt get dirty very fast honestly.