At the start of the story Tom's perseverance to his job is amazing. He stays home instead of going out so he can get all of his stuff done. He goes hard and gets a whole bunch done.
When the paper that may help his job and get him the promotion. He goes out onto the ledge without thinking twice and just goes out and gets the paper. If he didnt do that and just let it fly out the window the story would have gone a different way.
By the end of the story Tom's perseverance has helped shaped the story and has helped Tom out in the long run actually because now he wants to get back to his wife and turn his life around.