Cleaning makeup brush
One use makeup brush for your face and forget to clean it at times. It helps bacteria and fungus to grow on it. Which you will use without cleaning and put lots of bacteria to your face unknowingly. This may lead to many other problems like acne, pimples and what not.
I have recommendation for you hopefully you might find useful. It is one of the most useful things i have encountered recently. It is a kind of holder which prevents detergent leakages, which used to be a big mess .. you can see this gadget here