For me it's not about ever increasing volumes of clothing; rather, I find my preferences shift and change, which ensures that the contents of my closets are continually changing. Thank god for eBay and Goodwill.
Just a few more staples. I want to complete my wardrobe but I also don't want to buy unecessary items. For example for shoes, I just want a pair in black and another in brown, but I want to cover formal, semi-formal, casual, sporty.