Office cleaning only gets noticed when it slips. A sink full of mugs on Monday, bins still full after a client meeting, a washroom out of hand towel by ten. Each one is small. Together they tell your people and your visitors that nobody's minding the place.
The usual cause is a contractor with no real system. Cleaners rotate, nobody inspects, and the work that counts gets skipped first: the fridge, the meeting room whiteboard ledge, the shower drain in end-of-trip. Office and facility managers find out from staff complaints, not from the cleaning company.
With hybrid work, offices also swing between quiet days and packed ones. A fixed routine that ignores those peaks leaves the busiest days the messiest.