Well I am changing my ways since joining the forum. I used to duplicate because I couldn't decide on the colour, and it if was a good sale etc. Recently I made a pact with myself that I would only buy in a certain spectrum and this has helped. But for basics in certain styles I will do it - like tshirts etc. I am looking to give up my title of Queen Returna.
I like to duplicate an item exactly (same color) if I really like it a lot. Sometimes I'll buy 2 colors of a particular tee, sweater or jeans. I hate when I really love a particular cut/style of a tee for example and then I go back to order again and it's gone. This happens quite often I've found. So, if I really feel like it's a great fit, etc. and the price is affordable, I"ll get two so I can enjoy it longer or more often.
I do it quite a bit, although less often than I used to. I have several favorite shoes that I've purchased in both black and brown. I guess I'm trying to cover all bases.