I’ve had consistently good service from UPS, iffy service from FedEx, and rotten service from the USPS.
FedEx, for instance, required a signature for a package containing a $10 filter, but left a package containing a Hasselblad on the porch in plain view from the street. In recent times they’ve consistently delivered my packages to my neighbor.
USPS tracking info is frequently wrong or unavailable. You can’t trust it.
Amazon’s own delivery service is first-rate. Fast, accurate tracking, and they email me a picture of the delivered package in situ. I’ve seen UPS and FedEx drivers literally toss packages onto my porch on my surveillance cameras.