Why Did Banks Move Their Call Centres To India And Other Parts Of Asia?

One of the most frustrating things that banks have recently done is outsource their call centres to places in Asia.  Asian call centres are generally run by British managers but are full of people who have been on courses to learn how 'speak professional English', I've lost tired of how many times they can't help me because we don't actually understand each other.

The main reason that banks did it is cost, they can pay Asian call centre workers a fraction of their western counterparts.

Since the call centres in Asia have different time zones, they can be open at different times of the day to UK call centres, so no paying UK staff for anti-social hours.

Of course there is a serious problem with communication, the English language is complex and full of issues, I was once told by one of these operators that my home didn't exist.  Oh really, in that case I won't be paying my mortgage to them in future!