"Extend the life of your makeup by using disposable applicators to avoid the double dip. Makeup’s biggest enemy is bacteria, which are generally introduced to liquid products such as mascara by re-using an applicator. If you’ve ever had your makeup professionally done, you might notice that we makeup artists always use a new, clean mascara wand every time we have to dip into the product. We do this for the safety of our clients so that bacteria from one client isn’t transferred to another, but limiting exposure to bacteria also helps the products last much longer. The easiest way to avoid the double dip is to use disposable applicators which you can generally get at any beauty supply shop."
-Ann Merin, makeup artist who appears on TLC’s Wedding Day Makeover