Because the business side doesn't want to communicate on the 'success' of offshoring. Which, to be fair, isn't an issue if you pay the locals fairly, have a correct vulture based on good communication and clear vision.
I've worked for a French bank that messed up its tech offshoring badly, and is one of the _European_ bank that spend the most for its IT division, despite being nowhere near the top _french_ bank in revenue.