I always message the person before leaving negative feedback and even then it should be REALLY bad before leaving a negative. I am very proud of my 100% trade rating with over 800 feedback, but I also know that I am not perfect.
In your case, I would probably expect some type of communication if there is a problem with the card like that, but not everyone thinks like that. Something that would be a major problem to some people, I might not even notice or care about. I have had people message me and apologize profusely about a card's condition before sending and including additional cards. When I got the card in, it looked absolutely fine to me and I probably wouldn't have even noticed had it not been pointed out.
Point being that not everyone thinks the same way about conditions. Doesn't make either party right or wrong, just different ways of looking at life. I would not leave a negative unless I TRULY believed the person was trying to scam me purposely. Just my opinion.