USPS, UPS, FEDEX are all notorious for not being on time. This isn't new news, or shouldn't be new new to anyone that orders items online.
I order shit online and pay for 2 day shipping just to have it delivered in 4 days. Or priority shipping and it's here in 3 day. Or it's delivered in 7 days. Or 10 days.
He's a drug dealer sending out boxes to random USPS drop offs. Anyone thinking you'll get a package in 3 days time is delusional. I don't care what he says shipping times are, or what Target or Best Buy or any other retailers say their times are. It's all bullshit.
[EDIT] Apart from Amazon. I don't know how they do it, but for the most part, I ask for next day or 2 days, that shit is here. But, we ain't talking about Amazon now are we? lol