Masks are dangerous if worn improperly. They can create a warm moist environment on your face that promotes microbial growth. Also, the mask itself can get infected. Disposable masks aren't built to he reused and cleaned, so you can end up transferring the infection around on your mask if you reuse a disposable. Finally, the idea that masks reduce touching your face might be false, it's possible something itchy and irritating like a mask caused people to touch their faces more.