Opening an office is a completely different thing; there is an enormous difference between offshore contractors and offshore employees. That much, I'll agree with.

In the US, though, it's usually cost-driven. When offshore mandates come down, it's always in terms of getting more people for less cost. However, in most cases, you don't get more quality code faster by throwing more people at it. It's very much a case of "9 women making a baby in one month." Rarely are software problems solved with larger teams; usually, a single, highly skilled programmer will do more for a software project than 5 junior developers.

Not an projects are the same. Sometimes what you do need is a bunch of people. But it's by far more the exception than the rule, and yet Management (especially in companies where software isn't the core competency) almost always assumes the opposite.

If you performed a survey in the US, I would bet good money that in the majority of cases the decision to offshore was not made by line managers, but by someone higher in the chain who did not have a software engineering degree.