Last week I had all of my neighbors mail delivered to my house, not one piece, five pieces. Mind you I still haven't received my mail from that day.
I had an order that was supposed to be delivered to my work yesterday. We've been in the same 50,000 sq/ft building for 15 1/2 years and get deliveries from USPS almost daily. They sent the package back stating that we've moved and didn't leave a forwarding address.
What. The. Fuck.
If you've ever talked to the people that deliver for them, you can tell it doesn't take many "prerequisites" to become an employee.
There is a difference between skilled and unskilled labor, if the majority of your workforce is unskilled, I'm sure you can guess what the outcome of the final product would be, as opposed to a skilled workforce.