Yes those are all good scenarios. And it could be the lack of dedication the post office has nowadays. For it's workers. Which causes low mortality.
It's allot of factors that could hold your package up. Please keep in mind this is a processing plant. Meaning that your package is received, sorted, processed and picked up and sent to it's next location. Your package ( just giving scenarios) could be damaged, could be a low volume zip, ( your package isn't sent out daily) or could be on its way to it's next location and wasn't scanned or updated so you can see on your end what's happening. It also could be the shipping method your supplier choose as well.
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