Never worn one. On some of my husband's work sites they require hard hats which I have thought best never to interfere with by my presence which he seems to be OK with.
They do "investigate", though how well and how frequently is anyone's guess. Investigation, usually done post event, is akin to locking the stable door after the horse has bolted.
I’ve never been on a motorcycle, but I wear them for four wheeling and snowmobiling. That’s about it. Yeah, seems nutz not to wear one on a motorcycle lol.