The strange part is that the bigger the business, the less anyone checks. AWS and Azure became the answer nobody has to defend, so the invoice renews, and renews, and no one is ever asked to justify it. It stopped being a decision and became a standing order.
Cloud spend is rent. It buys you this month and nothing else. The same money put into hardware buys a machine that is still yours in year five.
For a steady, always-on workload the gap is wider than most people expect, and none of it is a secret. It survives because nobody sits down and does the arithmetic. Do it once and the file server, the database and the virtualisation host all start looking like things you should simply own.
Owning it is not free, and we will not pretend otherwise. It needs clean power, cooling, a UPS, backups, patching, and someone who notices at 2am when a drive drops out of the array. That is the part people leave out of the sums. It is also the part we do, for as long as the machine lives.