Not to mention the general public are not trained medical professionals who know how to properly wear and use a mask..
Well it is not rocket science to wear a mask.
The thing that never made sense to me was...OK everyone wear one, but then you take it off and put it in your pocket (therefore touching it with your hands). Then you put it back on when you get up to leave.
Of course, these masks are designed to be single use in the medical field, but early on you couldn't buy any and if you could they were like $2.50 a piece. So nobody is using them as they were designed, not because they didn't know how, but because they couldn't. Even today I still wear it til it starts to fray.
As time goes on it is understandable for things to change as knowledge grows, but I've also seen things seem to make less and less sense.