I work in the car business and while I can definitely buy and maintain a car for 10 + years I like leasing them so I'm in a brand new one every 2-3 years max. From my short experience with firearms they are relatively inexpensive and from what I can tell you can buy a gun for $600 or so, use it for 2-3 years and then trade it in for about half the price(hopefully more if you sell it privately) and now you have a brand new firearm without the scratches and possible rust that the old one had accumulated and maybe you are craving for a newer design or model that just came out. From these forums it seems like people don't generally like doing that. I understand that a gun can last you a lifetime unlike a car but I'm sure most firearms enthusiasts get the itch for new products fairly quickly but it doesn't seem to be common to be trade in your 3 year old 9mm or AR15 for a new model. Compared to most other products (like automobiles) the loss is only a few hundred dollars instead of thousands so why aren't most people doing this?