AIFA has rejected an application by the IFA Defence Union's Evan Owen to replace Chris Cummings as director general.
The industry body has been on the hunt for a new leader since June, when Cummings announced he would be stepping down from the post in August.
He will leave the role he has held since 2005 will join TheCityUK, which will promote the UK's financial and related professional services industry.
Owen, who has been a vocal critic of some of the AIFA's strategies, says he is "disappointed but not surprised" he has been turned down.
"It would have been nice to have an interview just as an opportunity to discuss the industry," he says.
Owen says he expects Association of Mortgage Intermediaries director Robert Sinclair to take the top job.
But he believes many IFAs have been put off from applying for the role because of a false belief anyone who has ever practised as an IFA is disqualified from entering the running.
"Lots of IFAs I know didn't apply for the AIFA job because they thought they weren't allowed, including IFA Defence Union chairman Alan Lakey."
Owen says he would have used his time as director general to merge AIFA with other industry bodies in a cost-saving exercise.
"We need to merge things. I would have looked for ways to save money for IFAs in these times of hardship.
"We must also realise we have an ever-decreasing pot of IFAs and AIFA will end up in a broom cupboard if we are not careful."
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