Earlier quoted context omitted.
You seem to forget there were and are companies like fedex and ups that deliver things just fine and don't have these issues. It might have something to do with how they train and pay their employees.
Let's not idealize the situation at other delivery companies. Delivering is not a dream job. It'd be interesting to see how much business is B2B and repeated addresses for UPS/Fedex vs Amazon. Amazon is likely to be distinct. High amount of one off consumers. Varying routes every day. Customers being away during delivery. Exactly what ruins a delivery company.
It's not your dream job. My last cab driver immigrated 16 years ago and has been driving 5pm-5am shift for the last 7 years. Full time delivery is a dream in comparison. I don't think he could send his kids to college on Uber.
It's healthy compared to desk work, doesn't require any extensive training, and relatively low stress.
Be cautious when predicting the behavior of others.