The hook
“Foreign customers and foreign bank receipts do not answer the whole Hong Kong profits-tax question by themselves.”
Hong Kong's official profits-tax guidance is based on whether profits arise in or are derived from Hong Kong from a business carried on in Hong Kong. That is a factual source test, not a customer-location shortcut. The dangerous oversimplification is turning 'territorial system' into 'foreign clients mean untaxed profits.'
The takeaway
A Hong Kong founder needs a source analysis, not a slogan.