A royal commission-style inquiry is probing the ASX-listed company after allegations emerged that it enabled suspected money laundering, organised crime, fraud and foreign interference at its venues, including The Star Sydney.
John O'Neill, who tendered his resignation as chairman late last week, told the inquiry on Monday that cleansing was needed after parts of the company's business went "very badly wrong".
"That cathartic moment requires as much cleansing as possible, and that's what we've attempted to do," said Mr O'Neill, who is also planning to step down from the board.
Many of Star's top brass, including managing director and chief executive Matt Bekier, chief financial officer Harry Theodore, chief casino officer Greg Hawkins, and chief legal and risk officer Paula Martin have left in recent months.
Further high-level resignations are anticipated, the inquiry heard.
Asked whether the resignations represented an extraordinary situation, Mr O'Neill said the circumstances required extraordinary action.
He said the board did its best to model leadership.
"We attempted to the best of our ability to get the message down to the line as what's acceptable and what's unacceptable," he said.
Star announced on Monday that Ben Heap will assume the role of interim chairman, while Geoff Hogg will become acting chief executive.
Earlier on Monday, Star director Richard Sheppard blamed some of the casino operator's failings on not refreshing management.
"The management had been doing things a certain way," Mr Sheppard said.
"There wasn't fresh eyes and a fresh approach."
Mr Sheppard urged more diversity on Star's board, including adding someone with a legal enforcement background, not a business background.
The inquiry was told several senior casino managers hid information from the board.
"We possibly didn't ask enough questions, but I can absolutely assure you that the board asked lots of questions".
The inquiry continues.