I brush the walls and floor after I vacuum. If I do it immediately before, the dust I want to vacuum up is all stirred up. I also brush some on days when I don't vacuum, just to get the stuff off the walls so maybe it will settle where I can vacuum it up. You'd think it would all settle, but it's not so different from airborne dust. Why would it stick to windows and walls and not settle on the floor?
If you have any doubts about how well mixed chlorine or acid are, reach for the brush. A few swipes this way and that will get things mixed. It's like stirring cream into coffee but on a massive scale.