In the cloud, costs are transparent, as you receive a single monthly bill. When you self-host, there are many hidden expenses you would need to track down (energy, admin, maintenance, etc.)

The figures in the article are for illustration purposes only and should be taken with a large pinch of salt. The author doesn't detail what hardware they are running, what EC2 instances he has selected for comparison and how comparable the storage statistics are. I would also love to hear the Finance Department's version of his calculations.

AWS is more expensive than self-hosting. However, it is not as skewed as the author claims. Otherwise, very few companies would be using the cloud.