Most office cleaning complaints are small on their own. A coffee ring left on the boardroom table. The kitchen sink full of mugs that nobody touched. Soap out in the ladies' bathroom by Wednesday. Add them up over a few months and staff stop trusting the cleaner, and somebody in the office ends up doing the job instead.
The usual cause is that nobody checks. The crew changes from week to week, the scope is vague, and the only feedback loop is an email from the office manager that disappears into a call centre.
That costs more than it looks. Visitors judge your business by the reception and the meeting rooms, and your team notices when the end-of-trip room smells or the carpet hasn't been vacuumed under the desks in a month.