You left out the best part. After all these savings, productivity drops precipitously. And it stays down, because what these Indian outsourcers are pushing (the one I worked with is Cognizant) is 'flexibility'. They tell the US company that they can provide a workforce that ramps up to handle any project you throw at them. But in order to do that, they 'train' a pool of workers and then rotate them off of the project. The result of this is that the workers on a project at any given time are by design never experienced in the particulars of the given system they're working on. They can provide absolutely no creativity to the process, and in fact, will spin their wheels on a wrong aproach for weeks before asking for help and revealing how little they know. They're only human, after all, and they've been thrown into a project cold and are being evaluated based on metrics that have little to do with actually producing working code.
In our case, the outsourced projects included custom in-house platforms. And the Indian workers spent much of their time watching videos of us teaching the first round of them our jobs. I know this, because I was hired by the contractors to be the one 'employee' that actually knew how to do the work - and who did the lion's share of it. That's the other dirty secret - they hire a few key ex employees to maintain a semblance of continuity.
Also, in our case, none of this really mattered. It turned out that the company was for sale, and the real purpose of the outsourcing was to make the financials look better for the sale to a private equity firm. The eventual buyers probably knew they were buying a dog - but not how much of a dog they were buying. Now that they've realized the extent of it, they're dropping their plans for an IPO and firing the rest of us so they can milk whatever profitability is left from existing customer contracts. The empty hulk will be abandoned when those contracts run out - and the private equity guys will have gotten their money back. Nothing lost - except a viable company and a bunch of American jobs...