If you buy electronics item, if you get defective product, you can't return it back. Instead the customer service will ask you to contact the manufacturer's service center within 7 days of delivery to get it replacement/repair. The service center people are often clueless and won't allow replacement saying they can only repair it. And they will repair with a refurbished part and give it to you.
I read of a case of a guy who bought a laptop from some not so popular brand, and it having some issues and amazon refusing to give replacement, instead asking him to go to service centre.
Then he had to drop everything and immediately travel 400kms to the service center to get replacement because that too was only possible within 7 days. He had to travel to the nearest metro city and then stay there for 4 days to get his laptop repaired... His now new laptop has a refurbished part...and he wasted 4 days of work, and extra expenses to go to the service center.
Even if the service center agrees to give replacement, they give refurbished products only. They will give you brand new product only if they can't repair or if they dont have refurbished product in stock.
Just to give an idea. Consider if you bought this 32inch 4k monitor for 45000 from amazon -
https://www.amazon.in/BenQ-Entertainment-Anti-Glare-Flicker-Free-Bezel-Less/dp/B082P93LSQ/
It is amazon fulfilled, but look at the tiny icon below it that says "Aamzon delivered" and next to it " 7 days Service Centre Replacement only" icon. If something goes wrong with your order, feel free to figure out where is BenQ's service center, and be hopeful that the guy standing there understand this process of amazon. And you get your refurbished monitor in time.