I could just be bad luck, man.
I did a trade with a gentleman on here. He shipped first, due to my feedback, but I ended up shipping 4 days later than I wanted to, because my two jobs happened to shift the schedules in which I worked about 12 hours a day. On top of that, even after wrecking my room, I couldn't find part of the gun I was supposed to send.
Thankfully, the guy was really nice about the situation, and I'll be sending it to him at a later point. I'm thankful the guy understood, and I know it happens.
Just chalk it up to bad luck, and be happy they all came through.