By Katie Holdefehr In the world of home maintenance and upkeep, there are some things that feel nice to replace—like when you switch out your pillow covers or buy fresh bath towels. And then there are those things that are crucial to replace (and often!). The items on this list fall under the second category. Hang onto these four household staples longer than you should, and you risk spreading germs, dirt, or dust around your entire home.