I should perhaps have added above that transliteration from other languages frequently causes problems. From Arabic, we get 'Mohammed' and 'Muhammad', which some people doubtless assume to be two different names or find themselves asking which is the "correct" spelling. More recently, with Chinese itself, we have had changes such as from 'Peking' to 'Beijing' and, from the subcontinent, 'Bombay' to 'Mumbai' and so on.
If the place was originally called 'Mumbai', why - apart from ignorance or our usual lack of consideration for foreign tongues - did we Brits ever decide to call it 'Bombay' in the first place?