Context This is a simple question, but it is hard to provide a simple answer. It has been asked by all companies plan to initiate their cloud practices. There are various cloud cost models on the market, including those from AWS, Azure, Gartner , etc. However, none of them can provide a simple answer to the question. The only practical right answer is: depends. It is said that one of large cloud providers hired a PhD in finance from Harvard. All s/he does is to figure out, make and tell a financial case/story for the company’s potential enterprise customers. Debate on “Whether Cloud Saves IT/Business Cost” When I led enterprise cloud practice initiations during consulting engagements with large companies, the debate on "whether cloud will save IT and business cost" was always on the table. Quite often the debate was about comparing “apple” with “orange”. The various stakeholders were never able to achieve an “agreement”. A typical dilemma is: some cloud-promot