For instance I always feel a bit stumped when a buyer has been slow to pay.
Or an item comes and is um adequate rather than the thrilling bargain I was hoping for.
Or if you have bought multiple items from one seller. Do you just cut and paste 'quick delivery. Nice item' 10 times? I am often tempted to have a laugh with these ones but suspect the seller would not appreciate 'Just as good as the last 9 items' type comments.