Schools and centres carry a lot of people in a small space. Hundreds of hands touch the same taps, rails and desks every day, and young children don't always wash them. When the toilets are left wet or the classroom bins are full at 8am, parents notice, teachers complain and sick days follow.
Cleaning has to fit the day, too. Contractors who arrive while classes are still running, or who change staff every few weeks, create problems for schools that need to know exactly who is on site and when.
Then there are the holidays. They're the only time to strip floors, steam carpets and clean properly behind furniture, but if nobody plans for them, the break passes and the work slips to next term.