Do you tend to buy the same clothing items over and over? Are you lured by striped tees and dark jeans only to bring them home to find you have almost the exact same item in your wardrobe? I know that happens to me. But sometimes when I'm at the store, I forget what I have at home. And I've recently realized that this is because I'm going shopping when most of my clothes are in the laundry basket, waiting to be washed. Just like we shouldn't go grocery shopping on an empty stomach, I think we should stay away from clothing stores (be they Goodwill or Saks Fifth Avenue) when we have empty closets due to needing to do the wash.
Since I've started the one in, one out routine, I've been better about not getting duplicates (and when I do, I put the old one out or return the new one), but I've noticed that I can run through my mental closet inventory much more easily when the clothes are hanging there and not piled in the laundry basket. And that helps prevent a duplicate purchase.