The reason that strikes me as most important is #2 "Letting Amazon focus on data center infrastructure allows our engineers to focus on building and improving our business."

Too many companies roll their own solutions when they could take advantage of economies of scale like this and let another company dominate the problem.

Obviously there are privacy reasons to own your own data but I don't think they outweigh the performance and efficiency implications.

> Too many companies roll their own solutions when they could take advantage of economies of scale like this and let another company dominate the problem.

Too many companies build their business completely reliant on a single service provider that can/will change focus, increase costs, terminate/change service offerings, or have unreliable service availability.

aws and performance :) Crappy performance and poor uptime is precisely why people move off aws.

So, um, why does Netflix always seem to be up/performant?

Because they actually know how to implement fault tolerant scale on AWS. Most companies don't have simian army randomly wrecking infrastructure. Many companies/engineers think they can spin up a few (or few hundred) ec2 instances and think they have solved resiliency.

AWS is a tool, not a bullet made of silver.

They are shifting capex to opex. The complexity of solution that can perform OK on aws is significantly higher then complexity of solution that runs on metal. There are use cases for which aws will never be a viable option. AWS in general is a bad option for anyone but Netflix (Netflix consumes over 30% of aws resources if they make a mistake that causes even 30-40% spike all AWS customers are f#$ed)

Thanks.