It's also just kind of how people are. You can't reasonably expect a large corporation -- which is just a big group of people who are all trying to make decisions and getting in each other's way -- to be able to make logical choices when they're subject to every large stakeholder's whim and every bit of incompetence that happens everywhere along the line.
Is it happening in a capitalist setting here? Yes. But it happens in all settings all over the world, so to suggest it's unique to this system ignores the actual nature of the issue (which is the Human Condition).
The downsizing and outsourcing is driven by incentives to remove cost from the balance sheet. If there's no incentive to do so wisely, if there's no disincentive against doing so poorly, people will inevitably make bad 'outsourcing' deals, just to have made them. Quality might take a hit, direct billings might skyrocket, products might have to be scrapped, etc. But if you don't fix the incentives, it will happen over and over.
Similarly, if you incentivize a person to make deals, if they have a stronger incentive to make deals than to make good deals (e.g. if they have no effective disincentive against making bad deals) bad deals will get made.