"the costs of using the cloud stack up once companies reach large scale. Dropbox, for example, shifted away from the cloud in 2016 to opt for a custom built infrastructure in co-location facilities. They saved $75 million over 2 years and increased their gross margins from 33% to 67% due to this change. Actually, recent research suggests major companies spend 75%-80% of cost of revenue on their cloud bills. Should large companies shift away from the cloud like Dropbox did? Is it too late for some companies to untangle themselves from it?"