Simply having the auditor's report conveys to your prospects that you're speaking their language. But meeting their needs at every level earns and keeps a client's trust and builds "brand" with every interaction. A focus on the customer is the most powerful way of winning and keeping that customer. This sounds like a marketing talk on purpose; marketing experts understand the importance of a consistent message of excellent results. And what is an audit but proof of consistency?
Marriage is like a game of chess, except the board is flowing water, the pieces are made of smoke and no move you make will have any effect on the outcome.
—Jerry Seinfeld