HSBC Holdings has lost at least its fourth senior Asia-Pacific executive in three months after the resignation of Nick Sibley, the head of personal financial services in the region, according to sources. Mr Sibley's departure follows the loss of Michael Smith, the chief executive of HSBC's Asia-Pacific unit, who resigned early last month to join Australia & New Zealand Banking Group. In May, Blair Pickerell resigned as chief executive for Asia-Pacific at HSBC Investments (Hong Kong) to join Morgan Stanley as head of Asian investment management. A source said HSBC's Asia investment banking head, Steven Wallace, also left early this month to join Citi. A spokesman at HSBC declined to comment on the issue. Analysts said the changes at the top would hurt staff morale at a bank that has been noted for the long-term loyalty of senior executives, many of whom have been known to spend their entire careers at HSBC. That spirit was seen as a key to the lender's successful expansion from a Hong Kong local bank to becoming the world's fourth-largest banking group in terms of market value. A source said Mr Sibley had quit because of company politics. It was also because he had found himself facing less opportunity for promotion, the source said. Mr Sibley could not be contacted for comment. 'After a series of acquisitions by HSBC, the bank has kept talent from the acquired units. This has led some original staff, such as Mr Smith or Mr Sibley, feeling frustrated as that reduces their chances of being promoted and they look for alternatives,' the source said. Mr Sibley, who used to be in charge of product management in the Asia-Pacific, had also run the credit card business, deposits, wealth management and sales after the bank's restructuring of personal financial services at the end of 2005. An analyst from a European bank said it was in the nature of lenders to see high turnover given the recent robust financial market. 'It's a matter of whether they lose more talent than their rivals,' he said. The bank's performance might not be affected despite the changes at the top as operations now depended more on the system as a whole rather than on individual performance, he said. A source said Sandy Flockhart, who replaced Michael Smith as chief executive of HSBC's Asia-Pacific unit, will start in his new post in Hong Kong next week.