For me, this was a key reason I cancelled Prime.

In the 90s and 00s Amazon would fix things. The last time Amazon lost a “delivered” package they told me that they could do nothing about it. My ticket got escalated a few times and they offered a discount on ordering a replacement. I just did a chargeback with my credit card. I was frustrated with Amazon because I probably ordered 30 things a year for 10+ years and they trusted their driver over me saying I never got it.