The expiration date on your cosmetics isn't just there to con you into buying more makeup. Though some products may last longer than advertised (usually powders), in general makeup expiration dates are worth paying attention to, especially when it comes to liquids that go around the sensitive eye area. We're talking about you, mascara! An old mascara tube is not only a breeding ground for germs (especially if you pump the brush — don't do this!), but it's also more likely to clump and flake. As soon as you open that tube, the product inside starts to lose moisture. Remember how lovely it feels to open a fresh mascara and glide on the smooth liquid formula? You owe yourself that treat. If your mascara isn't finished after three months, bin it and buy a new one. It'll make the world of difference.