This is a minor pet peeve but, in my opinion, a serious sales failure. I went to Dell to order some computers, had them in my basket and a little while later, my session timed out and my shopping basket was empty. Why on earth would someone walk up to you in a store and take everything out of your shopping basket! amazon.com, for example, never does this. My basket is there for eternity. I can think of no reason to empty peoples’ shopping carts unless you have a major change in price or availability. It should not be necessary to create an account for this either. A cookie is a cookie is a cookie.
It is nuts to make it harder for people to buy your products. I think Dell has the disk space to cache my shopping basket until eternity or so.