So true. I also had 100% until recently. I sent an item via Australia post, which arrived damaged (a $7.00 Hotwheels car). Instead of contacting me, the Buyer just left negative feedback. I emailed the buyer and told him I was disappointed he did not contact me first as I would have refunded the item. If he had bought it from an online store and it arrived damaged, you would contact the store for a replacement or refund..right??. I was very polite (I have worked in customer service for 30 years). To my surprise I received an abusive email reply - here is a little of it......

"STOP blaming Australia Post.......Im SICK AND OVER people damaging MY PROPERTTY then blaming others.
Take some responsibility.
ITS ALL YOURS.

Your feedback will remain forever just to teach you a lesson in disrespecting other peoples property.......Nothing you can do , can bring back my car to being WHAT YOU SAID ,YOU WERE SELLING. This was a very rare item.
You may decide to refund the full amount, and I will revise the feedback otherwise..enjoy!"

I do not have a problem with the feedback system, but I think there should at least be a mechanism in place where a buyer needs to at least make contact with a seller first to resolve any issues before negative feedback can be posted. No contact at all does not give the buyer to rectify any unforseen problems like damage during delivery. Unreasonable-----full of it buyer!!! In view of his reply, I am no longer interested in offering a refund. I will just "enjoy" my feedback as it stands.