Next to zero issues with deliveries here.
Only two problems I've had in years:
1) Ordered something from Home Depot. They sent it via OnTrac. Ontrac claimed they delivered... like at 9pm. I got the notification, looked all over for the package, nowhere. I told HD no delivery; they said bs, our shipper says they delivered! I filed with my credit card.
A MONTH later my cc says "shipper says they delivered". I call HD and ***** them out, they send me another package. THAT VERY EVENING lo and behold my original package, dated the previous month, shows up. When the new package came from HD, I kept it - it took me hours to deal with this.
Ontrac sucks.
2) Ordered something off of ebay, paypal pay. It got delivered... supposedly. I complained and paypal says shipper showed that the tracking number was delivered.
I went to the post office, and they said yes, it was delivered, to this address: ***** I'm like what, that's not my address. Yep, the shipper sent it to the wrong address, right zip code. I'm done with paypal, that's the last time I'm screwed by them, because of course you get one appeal and their check that the shipment made it to where the shipment was sent succeeded, but not that it was sent to me, and they closed it. I closed my account with them.
#1 is on OnTrac and HD. I'm somewhat leery about ordering from HD because of this, but still do it from time to time. If they screw up, I'll do what I can to get my goods and maybe more for my efforts; if they want to step up and be good for the customer and not waste my time, I wouldn't need to keep their consolation gift.
#2 obviously isn't USPS's fault, and thanks to them I actually knew that I got screwed (the address where it was delivered didn't respond to me query about the package; I think they were in on it somehow or just didn't give a $%#@).
Otherwise: our USPS here is great. No complaints by me, though people on NextDoor complain about everything. UPS is fantastic. Often comes in the man gate and drops things at the doorstep but more often leaves things at the gate or just inside the gate. No theft issues (yet). Fedex is very good, not quite the extra mile but no complaints.