The feedback system that eBay uses is both simple and genius. Everytime an item is bought from a seller by a buyer, the buyer leaves feedback for the seller, and the seller leaves feedback for the buyer. Feedback is a short statement about how the transaction went. It can be either positive (for a good transaction), neutral (for a decent transaction with a complaint), or negative (for a deal that went very wrong).
Unfortunately, the way eBay is set up, buyers are expected to pay before the item is shipped to them. It would be logical then, that the seller would leave his feedback for the buyer after they pay. Most sellers however, don't leave feedback until it is left for them. This is because they want to make sure a seller is leaving good feedback before they do the same. Leaving negative feedback for a seller gives them a black mark, and they are likely to return the stain to you, whether or not you deserve it. In most cases, it's best to talk it out through email with the seller, and try to smooth things over.
Positive feedback should be left on most deals. The simple test is to ask yourself: "Would I buy from this seller again?" If the answer is yes, then you should leave positive feedback. If you become more serious about eBay, you should start using ready made feedback, and just copy and paste 2 lines of generic compliments for the deal : "Product is as advertised, great packaging. Would do business again!"
Neutral feedback is tricky. Even though a neutral rating doesn't count against a user's feedback score, a neutral rating means that one of the parties had a complaint about the deal. If you're unsure about whether or not you would do business again, then you want to leave neutral feedback. An example would be: "Good item but terrible communication from seller."
Negative feedback is the most mis-used type of feedback on eBay. You should only ever leave negative feedback if you feel that you were cheated by the seller. If after a long period of time you still don't have your item, and the seller is not replying to your emails, then you should leave negative feedback. Similairly, if you received an item that doesn't work, and the seller refuses to give you a refund, then you should leave negative feedback. Even though you might be angry, remember that level headed professional feedback will have more impact than one written in all caps. Something along the lines of: "Received my product after 3 months, and it was not working. Seller did NOT return my emails, and finally wouldn't give me a refund. Be warned." should get the message along clearly.
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