What is the enormous selling points that I am missing when I'm faced with this confusing mess?
I'm not trying to crack down on the company here, I just don't understand why they are the best.
First of all the Amazon SE is a complete joke compared to Amazon UK and US. With a broken design and much smaller selection. That being said, as someone who occasionally orders from Amazon SE, I'd say price, selection of certain niche items and delivery times are the reasons. For some items Amazon is very cheap. Recently ordered a book that cost 500 SEK on Adlibris or Bokus and 350 SEK on Amazon. Another book I wanted had a delivery time of 10 days from Adlibris and 24 hours on Amazon. Same with certain electronics. A DAC I'm currently considering is 20-25% cheaper on Amazon SE compared to any other Swedish site. Also if you want some cheap knockoff crap from China, Amazon generally has faster shipping, no tarrifs and much easier returns than aliexpress and friends.
But in general I only shop on Amazon if they are much cheaper or the only site that has the thing I need.
Before Brexit I frequently used Amazon UK. They had both good prices and fast shipping to Sweden. Same with Amazon US. I would still use them if it wasn't for the import charges.
That's it. There is some competitive pricing, almost predatory, but personally I keep going back to Amazon for customer service.