Window sills act like little shelves where outside dust and pollen land first. If they’re ignored, that dust builds up into thick layers. Each time you open or close the window, or when wind blows, it gets pushed further into the room—onto curtains, floors, beds.
A quick wipe of sills with a cloth while you’re doing basic dusting catches dust at the border. You’re stopping it at the gate instead of welcoming it deeper inside.
It’s a small area, but regularly cleaning it noticeably reduces how quickly the rest of the room gets dusty again.
