Johnny's father was a janitor at a business in the World Trade Center. He worked long hours there, and he always did a great job. Every floor was perfect. Every window was spotless. Every trashcan was emptied daily. He was a hard working man.Every day he'd leave for work early and he would return late in the night. He always put in overtime at work and provided for his family the best he could.As the years passed, Johnny's father grew older, he became less able to perform his duties at work. He attempted to get Johnny hired on to help him with the cleaning. His boss agreed, and Johnny was hired as another janitor.Things were going great for the two. They were making a decent living and were able to split the work between two people. Johnny learned all the tricks from his father, and faster than anyone had ever seen, he mopped the floors, he washed the windows, he emptied the trash cans. He even took on extra maintenance tasks with all the free time he had at work.One day, Johnny and his father were washing the outside of the windows, and they quickly became frustrated. There was a mark on the window that would not come off. No matter what they tried. They scrubbed it with soap and water. They tried spraying Windex. They tried many other cleaning solutions, but not matter what they did, this mark would not come off. They tried at it for weeks to get the mark off the window, and failed every time. They became obsessed with it. Neither of them could sleep at night.One day, late at night, Johnny got an idea. He headed into work to see what he could do about this mark on the window. When he got there, he discovered his father was already there, and had cleaned the mark! Johnny asked his father how he cleaned the mark. What did he use?His father would never tell him. He wanted to keep his secrets to himself, but as they grew older, his father became ill. As he lay on his deathbed, Johnny asked him once more, and all his father said was, "The glass is always cleaner on the other side."