It works differently where I live. I have my faithful regulars who never/seldom miss a clean, plus some shops in town. I have many more who ring me when I'm needed.
The number I have of these latter types ensure that I am kept busy enough most of the time. December is manic (need to work 7 days a week to keep up), then January is very quiet (no-one has any money after xmas and I am knackered from December anyways so I don't mind relaxing a bit).
It all balances itself out over the year, so I am happy enough.
John