He said recording all calls - and asking for the company's recording - were also good tactics in keeping dealings straight.
The boss of a firm fined $250,000 for the unlawful antics of call centre staff says the put-upon phone workers should be recognised as critical to any business. "If you can't engage with your customers you'll never be successful," says Slingshot's chief executive Mark Callander.
Mr Callander has front-footed the company's response to a $250,000 fine handed down last week over 50 charges under the Fair Trading Act.
The fine covered unauthorised access to rival Telecom's database which it used to switch across clients.
Mr Callander said Slingshot had addressed problems from 2009-2011 linked to the charges by streamlining its systems and restricting its growth.
He said the company also no longer contracted out any frontline contact with the public. That allowed its values to be directly passed to staff and gave more control over the way customer relations were managed. Phone and internet users' advocate Paul Brislen said complaints about Slingshot had fallen in recent years and it had joined the Telecommunications Dispute Resolution service.
Firms were taking call centres back inside the business because of the importance of staff interactions with customers.
