USPS is not the only shipping outfit 'employing' the signature-required BS estarky7 describes above.
FedEx drivers now sign for such delivered packages themselves, always illegibly, to avoid any accountability for packages gone missing.
Since cussing-out my UPS driver a few months ago, he now leaves all packages at my driveway entrance 200 yards from my house; the packages easily visible from the (busy) road, but not visible from the house. Makes me wish I'd kicked his UPS ass months ago, rather than just cussing him out!