Looking over the comments and replies here, it seems everyone has their own version of "the real reason Amazon was successful was X..." My own conclusion readi

Looking over the comments and replies here, it seems everyone has their own version of "the real reason Amazon was successful was X..." My own conclusion reading this is that Amazon was just highly competent across the board. They were online in the mid-90s. They were quick with shipping (eventually, if not right at launch). They were competitive on pricing. They quickly had a huge inventory. They had the "you might also like..." algorithm that's impossible to get from a print magazine. They had online reviews. They offered Prime in 2005.