Most kids get to experience the horrors of using a black light to see germs in elementary school science class. While that hand washing black light experiment did teach us how important it is to keep surfaces clean and keep our fingers to ourselves, most people wouldn't willingly torment themselves by using a UV light to show the bacteria on their hands.
That said, getting a glimpse of the dirtiest surfaces we touch can be an educational experience. Even the surfaces meant to keep us clean can become covered in germs. Luckily, soap and water are a great way to maintain personal cleanliness throughout the day.