dust and fluff
Ever noticed how dust and fluff come in selective colours? If you have a pale carpet and light coloured furnishings, the dust is brown or black. If you have a dark carpet the dust and fluff that collects or falls is white. Pilling on white clothing is always dark, so it's highly visible. Pilling on dark clothing is always white, so it's highly visible. Both mean careful shaving with a twin blade razor or lint remover. Dust bunnies under beds and in corners are always grey. Always.