I was just going through the mail this morning, and got a medium size envelope from a large credit card company. When I picked it up it was a bit thick but it was soft like there was something in it besides the stacks of normal rules and regulations. I bent it a bit, and thought well maybe this one is different then the others, and opened it hoping to get the free thing they sent me. Well it was the same garbage as always except that they included one sheet of bubble wrap this time for no reason at all. Ok I am writing here to say that there is a very good reason for this. It was included for a reason.To get me to open it. If you wonder why you are constantly getting envelopes in different colors, shapes, sizes, text, etc from these credit card companies, it is because these banks are constantly split testing their offers. These banks know their customers. They have done the research. They know how many males vs females open the mail. They know how many of us open the mail above the trash can vs in front of the tv. They know it because they are constantly trying to improve their responses, and are constantly adapting their offers. When our responses change, so do theirs. Lesson here is make sure we are still split testing, and constantly trying to improve your campaigns to adapt to changing conditions in your markets.