As a USPS employee I cannot speak to your situation. I can only tell you that there are good people working their asses off in the processing and distribution plants to make sure that mail is delivered to the recipient in the least amount of time possible. So while you want to gripe about us, remember that if you call our customer service you'll speak with someone in the US, probably a customer service supervisor in the station who handles your mail. Try that with the other common carriers. My personal experience with the other common carriers is that you'll speak with an international call center who will lie to you. of course, YMMV and if you don't use the USPS good luck.
My wife can attest to this. We were on vacation in Alabama when she got word that her new tablet/laptop/whatever was to be delivered while we were gone and a signature was required. She called the FedEx number and the guy (probably in India) literally wouldn't help her either change the delivery date or any other suggestion she asked about. She couldn't even get the phone number of the facility that would be delivering it. She finally got word somehow that if we could make it back before Monday closing time, she could probably pick it up at FedEx's facility in OKC. We made it in time and she got it picked up.