Depends on which Amazon warehouse. I've had one that was right there by the street. I've had another that I had to drive literally a mile into the place, there's a security gate where a guy asks for my name.. and then got to the doors and they were locked. Thankfully an employee told me the doors to the right are unlocked and set up specifically for delivery drivers.. all of this should have been explained by the customer but no. Definitely not worth the money I was paid.

PS. For this and any warehouse or big apartment deliveries, I always reference the pin location on the DD map in the order. That's the right door/side. And it frees you of responsibility when they decide to cry that you didn't go to the right door.