It's a job few people want to do, let alone keep doing.
In fact, some cleaning companies are relying more and more on student labour and workers coming and going, than retaining "career cleaners", according to OCS Australasian managing director Gareth Marriott.
Despite this, Marriott said the industry employed 40,000 people in New Zealand, and injected $1 billion into the economy each year.
To stand in the work shoes of a cleaner, Marriott swapped his briefcase for a mop and a bucket this week, and joined cleaning staff for a shift at the Rotorua Central Mall.
Marriott helped scrub toilets, remove rubbish, mop floors and clear tables, from 3pm until midnight, to better understand the working conditions for the 4200 workers he oversees in New Zealand and 1000 in Australia.
Marriott calls them "unsung heroes".
"These are the hardworking teams of people that put our worlds in order without us even knowing.
"The hours our teams work are pretty unsociable, they work through the night and often on public holidays to accommodate our clients' needs. It can be thankless work."
Marriott and the team also cleaned BNZ, Mitre 10, the Fire and Emergency New Zealand National Training Centre, Bidvest, and Tipu Ora, under the direction of leader Eris Huys.
Rotorua branch manager Averill Baird said staff giggled when they found out Marriott was joining in.
"'Is he going to do it properly? Is he really?' They said... We told him not to forget to drink some water. He laughed but we had to tell him we were serious."
Huys said she was initially nervous about telling the managing director what to do.
"But then we had a laugh with him, and he was really friendly so we relaxed. We realised he was just a normal everyday person, who wasn't afraid to get his hands dirty."
Marriott encouraged other senior managers to also take a hands-on approach, to understand their business from the bottom up.
"If I'm not prepared to do what these people do, why should they do it?"