I suppose you could argue someone who operates a till in a shop could chat on the phone whilst they are scanning stuff.
On the phone? No they are in a customer facing role and part of that role is to provide customer service. They do manage to chat to the customer while scanning which requires the same level of concentration as chatting hands free on a phone.
A teacher could chat away whilst the kids were doing set work.
This does happen yes. Either chatting to a colleague in the room or chatting on the phone. I know some of my teachers certainly carried out phone conversations while we were getting on with something that didn’t need their input.
People in factories could chat while they were assembling/making stuff.
Many do. Some are allowed. Some aren’t. Some can’t due to wearing ear defenders.
What is it about cleaning that means they don't have to focus on their job?
What it is about cleaning is that it doesn’t require high levels of focus. It requires eyes and one or two hands. Leaving the brain and lips free. My brain and lips generally occupy themselves by singing, working out my current childcare issues, wondering what colour to paint my garden shed. I get an immense amount of proper thinking done while working. And this is all while listening to music at the same time. I’m not at all a phone chatting person, I like being a cleaner in no small part because it means I don’t have to talk to lots of people, but o would have no difficulty in completing my work to the same standard if I was talking on the phone instead of singing and planning as I do.
My cleaner earns more per hour than my daughter in her graduate entry level job.
Your cleaner probably charges more than your daughter earns but I suspect she doesn’t actually take home more by that much if at all.
And my daughter can't make personal calls for half an hour whilst she's working.
That will be because your daughter is employed and signed a contract agreeing that she wouldn’t talk on the phone whilst working.
Bracket she is supposed to be - you know - working.
What does she work at? You could always suggest she become a self employed cleaner.