But yeh, the dental floss, I can see that, and it's not that disgusting, if there is no need for cleaning then there would be no cleaner to see the mess in the first place. The need for the cleaner in the first place is what creates the job opportunity!
Disposing of someone else's rubbish in the proper receptacle isn't cleaning.
It's enabling bone idleness and delusions of grandeur.
When you throw out your own dental floss or snotty tissues or razors that are no use to you any more you are doing what is called clearing up after yourself. It's what people with self respect and respect for others do in their own homes.
Cleaning otoh is using a sponge or mop or hoover and rendering surfaces clean and sanitised. Or cleaning bedding and putting it back freshly laundered on beds.
People clean up after residents of care homes because they can't do it for themselves. It distresses many older people that someone else has to do so much for them that they used to do for themselves and for their families.
There is no excuse for able bodied people leaving body fluids - vomit, blood, pee, or shit stains - in their home for someone else (perhaps some young woman from 'abroad' lacking a sense of perspective 
with notions about her station, unlike the older women of yore who just sucked it up because unlike in their own homes they were being paid - a pittance - for 'sucking it up'). How do people live for days or even weeks in such squalor?