The customer friendliness is 1. free fast shipping 2. they will cancel and refund things 3. if you make multiple orders they'll combine them 4. the website loads really fast.
Competitors have gotten better at many of these, but it's still hard to impossible to cancel orders many other places, and if I have to chat to Amazon they still refund and replace things very easily.
I have used amazon.com.au and noticed the selection is pretty bad there. amazon.jp is great though, and worldwide shipping is amazingly fast. The customer service is even more important there because Japanese companies hate cancelling things or special requests (omotenashi/"Japanese customer service" means you do what they tell you, not the other way round.)
Competitors have gotten better at many of these, but it's still hard to impossible to cancel orders many other places, and if I have to chat to Amazon they still refund and replace things very easily.
I have used amazon.com.au and noticed the selection is pretty bad there. amazon.jp is great though, and worldwide shipping is amazingly fast. The customer service is even more important there because Japanese companies hate cancelling things or special requests (omotenashi/"Japanese customer service" means you do what they tell you, not the other way round.)