"But why should they do that???"
Just ask IBM. They are moving most of their software work to India. That includes the writing scope of services (specifications). If they can have it done cheaper they will do it.
Isn't IBM a chinese company anyway now? Lenovo and such?
Besides, the point is, if they can get it done cheaper in India, why shouldnt they. IBM is under no obligation to pay more for the same services, frankly.
If you're writing specifications for a solitaire game, that may be one thing; if you're writing advanced algorithms for chemical assays, that may be something else.
Einstein could not have just handed off the idea of general relativity to an Indian firm and said, "create some software to simulate these theories." He'd have to write the specifications himself.