I have noticed that if I pay my bills when I agreed to pay them - the company which loaned me the money doesn't bother me much. I keep up my end of the bargain and things go rather smoothly.
One of my first corporate jobs was that of a bill collector. Without going into too much detail - It isn't easy to be on the phone 8+ hours per day hearing all the tragic things which cause people to be late with bills, day in and day out. Repo'ing someone's car, foreclosing their home is not a pleasant thing to do. Emotionally - it is not a very rewarding job for the most part... But those customer's who spoke with me, made arrangments and kept those arrangments didn't get continued phone calls/letters.