I agree with Furnace Cleaner: to save time. I prefer to dedicate my resources to doing the work of the business. Outsourcing cleaning helps to accomplish that, while also providing a clean, professional work environment.
I think one of the main issues is that it isn't anyone else's job description. If it is a one person business that person probably doesn't mind doing the cleaning. When you have a dozen or so then it is more likely the employees are office staff, sales staff, management and warehouse people and not consider cleaning the office part of their duties. Can you really ask a sales person to vacuum the carpet?
We do have a cleaning service for that exact reason. In the factory part of my business the guys don't have a problem cleaning up their workspace but in the office our staff doesn't consider that a part of their job description and doesn't like having to do it so last year we hired a cleaning service.
When developing your content/ad/marketing promos - dig deeper than save valuable time.
Show your prospect what will they do with that time. More time to watch their kids play ball. More time to enjoy go boating, golfing, pursue their love of painting or writing.
Hire a cleaning service and you are hiring a safety expert. One who will not only do 'surface' cleaning but assure that your family is safe from allergens like mold and dust in all corners of your home.
Hire a cleaning service and you are hiring peace of mind knowing your home is always clean and safe no matter how busy you are.
Hire a cleaning service and you will be able to be more social by knowing your home is always 'guest ready'.
Just a few suggestions.