F*ck usps!

I sell parts that go from Austria, to Australia, for the past 13 years.
In all that time i never had a customer get back to me with a complaint, or problem, with an item being damaged in shipping, because i pack to survive all kinds of abuse within the shipping system.
I will bet a dollar to a doughnut, that your seller did a piss poor job on packaging that part in the box, to begin with.
Everything needs to be packed tight, to survive all the automated conveyor belts, and all the handling on and off trucks that a package needs to go through in going from point A, to point B.
Sorry in your getting a damaged part, but if it wasn't packaged properly. Firstly, blame your seller, and not the mailman, FEDEX, or UPS boys and girls.

I agree mostly to this but....
had good luck shipping fedex express, USPS cept some items got stuck in customs forever mostly Canada, RPS lost things and I once had a package I nick named boomerang because it went from TN to a state and back and forth from that state to another state back and forth for a month, excellent service with grey hound bus and much cheaper for large parts, I shipped two heavy car doors ups and had insurance the customer prepaid and the UPS guy when I shipped them noted how well I always packed items but the customer got his doors and they were smashed in and crushed as though they were run over with a fork lift and he sent photos to me via email omg it was horrible and shocking he said he had had a lot of problems with ups damaging his packages so it seemed to happen locally. but they refused to pay him his insurance money with some flimsy excuse. ... I used to work for FedEx Express in Memphis and was a courier here in Nashville. I KNOW how to pack a package. I know what a package goes through in his process 8-)