I find that it is still pretty reliable but I also held the wrong understanding of what the guarantee. "Prime Two-Day Shipping refers to the amount of time it takes for your item to arrive once it's been processed and shipped. Some items have longer processing times than others," the guarantee reads.
Some Amazon customers are frustrated that their packages are arriving late — and it reveals a giant misconception people have about Prime
Customer complaints around the slowing of Amazon Prime deliveries reveals how much confusion there is surrounding its two-day-shipping guarantee.