You haven't heard anything out of your customers for awhile so you assume that everything is fine. Then one day you get that phone call "Sorry but we're changing services." You find out that there were things that never got cleaned (Whether they were part of the deal or not) and that everyone was just ready to make a change.
Don't let your customers "suffer in silence." Actively engage them in communication. That way you don't lose a customer and they feel like there is a line of communication open should they have problems or questions about the cleaning. I'm not saying call or email everyday but stay in front of them whether it's cleaning related or to say "Happy Holidays".
Plus engaging them in communication will more often than not lead to more work for you and more profits.
And if you were wondering...yes I'm speaking from experience...Hope this helps.