This is hindsight. When Amazon started, it was a pure e-commerce play. It later evolved into the company you describe. For example, they signed a bunch of excl

This is hindsight. When Amazon started, it was a pure e-commerce play. It later evolved into the company you describe. For example, they signed a bunch of exclusive supplier agreements for their store. Then, when they launched Marketplace, they got sued by some of those suppliers for breaking exclusivity. E-commerce success created the cashflow and in-house expertise that allowed Bezos to explore other markets. Some succeeded, like Marketplace and AWS. Some did not, like the A9 search engine and Fire phone.