Once upon a time there was a rocket-powered squeegee and her name was Chartreuse. She was the best squeegee in the world and all the skyscraper owners hired her to clean their buildings, especially the owners of the Empire State Building, which she could clean in 20 mins flat.
Unfortunately the price of rocket fuel was going up, which made it hard for Chartreuse to stay in business. She would charge $200 for the Empire State Building, but had to pay $199 for rocket fuel, which left her only $1 to live on. So she decided to up her rates.
She went to Empire State Building owners and told them her rate was now $250. They made billions every year but were super cheapskates so they declined to retain Chartreuse’s services. The Empire State Building got dirtier and moldy and mossy and fuzzy and disgusting.
After 3.5 years and the building dirty beyond recognition, the owners caved and begged Chartreuse to come clean the skyscraper, even at the higher rate. The squeegee was savvy, though, and decided to charge $500 since it was so filthy. The owners balked, but agreed.
She flew up and down the Empire State Building using her rocket power and soon it was 99.9% clean, all except for the last strip, when…Chartreuse got stuck on the point of the top of the tower. The owners were impatient, threatening to withhold payment until she was done…