People don’t wash their hands after using the bathroom nearly as frequently as they should.
Part of the reluctance, I reckon, may be to do with having to grab hold of taps which have just been handled by someone who is only marginally cleaner (having at least used the taps).
Push button taps allow you to get water and avoid touching the tap a second time, but their automated stop wastes a lot of post-wash water. Similar proximity switch versions are complex and fragile.
For added hygiene, today’s invention is a tap which is switched on and off under the water outlet.
In this way, the tap itself is always kept clean and can be closed immediately handwashing is complete (and rinsed by the last of the falling water).