With a record-breaking 226 consecutive wins in the ratings and a string of scandals in his wake, Alan Jones will leave 2GB as the most successful, influential and controversial radio host Australia has ever known.

But while many listeners and conservative politicians will mourn his unexpected decision to resign on Tuesday, few inside Nine Entertainment Co's headquarters will be doing the same.

Outgoing 2GB Breakfast Show host Alan Jones.CREDIT:NICK MOIR

Indeed, his decision to step down for health reasons - just a year after signing a new contract - papers over the financial cracks that have appeared in his program.

Jones’s resignation is an "out" for a media company paying millions of dollars a year to a broadcaster whose controversial comments about New Zealand Prime Minister Jacinda Ardern last year cost his breakfast program large sums of money from advertisers. Some of that revenue has never returned. Nine also owns The Sydney Morning Herald and The Age.

Jones, who last year re-signed a new annual $4 million salary, cost the company the same amount (if not more) in advertising dollars when he said in August Ms Ardern should be given "backhanders" and have a sock shoved down her throat.

His comments about Ms Ardern caused more than 80 brands including retailers Coles and Bing Lee to leave the show immediately and that figure continued to increase despite a belated apology.