My friend spent several years working at a local city college. She couldn't help but notice the incredible filthiness of the blinds in her classroom. It was made worse by the fact that there was a high ceiling, and they reached all the way to the top.
When she went to her supervisor to complain, he said he would make a request. They waited for a year. Then they waited for another year. But shortly after year three, a custodian entered the room and searched around for the blinds. My friend imagined the way her mother cleaned the blinds--take them down and soak them in the bathtub in soapy water. That works well.
The custodian had a different idea. He got down and started wiping the slats at the bottom, and then he moved to a standing position. When he reached as high as he could, he turned around and left. Now he could have stood on the windowsill and reached almost to the top. But it had never been done that way. It had always been done this way.
So this year, when they request a new cleaning for three years from now, they're going to ask for the tallest custodian. It won't really solve the problem, but it will at least come a little closer.