USPS always just leaves a note that they will try again to deliever WHEN I WAS HOME AT THE TIME. 50% of items from USPS always gets returned to sender due to unavailable times. UPS and FEDEX seem to deliver my items 90% of the time.
I live in NYC and don't have a car. I'm not walking a mile to my local postal center to pickup the 20lbs bag. I Ordered from Amazon so that I wouldn't have to.
To their credit, Amazon overnighted a new order which thankfully got delivered by UPS instead.
USPS on the other hand, delivers every time.