[vonmoltke]

That is the use case that AWS is best for. That is not the use case covered in the article, though. The use case being discussed is that for a cluster of always-on machines with a fairly consistent load. If you have a minimum baseline load on your servers, fulfilling that from AWS, or Azure, or similar services doesn't make financial sense. Colocated (if you don't mind dealing with the hardware) or leased (if you do mind) servers for your baseline load combined with cloud machines for load spikes makes the most sense.