This concept just hit me the other day: one is enough. There is no need to stock up on multiple items of clothing, shoes or electronics. One is all you can use at one time. Even though you have two ears, two eyes and two hands, you can only listen to, read and type one thing at a time. You can only drive one car at a time, you can only ride one bike. This idea has freed up a lot of mind clutter, and the desire to stock up on items that I will eventually forget I've stocked up.