Short term cost savings. The only question is whether or not the companies will come to their senses before the entrepreneurs in China and India, to whom we have given all our trade secrets, will become competitors to the short-term, MBA-driven companies here and successfully eliminate them, completing the destruction of the US economy.
OR it could be that the US companies want to undermine the US middle class, having sucked all the cash out of them that can be managed: and the companies are trying to foster a replacement middle class in the "developing" (and younger!) countries, in order to replace the aging baby boomers as key consumers.
I have written several vanities on this; FReepmail me if you want more info.
Full Disclosure: I am sick of hearing about "Americans who can't do science and engineering" myself, as I have an earned doctorate in molecular physics.
Cheers!
But you have to admit, it's ironic that it's our business "elites" that are making this country ripe for socialism.