One of Aegon's largest adviser clients has said a lack of interaction with clients made the departure of Aegon's platform development boss "inevitable".
Chief digital and transformation officer Richard Denning resigned from Aegon at the start of this week, citing a desire to "take a break from corporate life".
Darius McDermott, managing director at Chelsea Financial Services and a major client of Aegon, said: "I am not surprised to see Richard Denning depart.
"There has been a lack of engagement with clients and a lack of foresight. They are taking remedial action now but it is not something that can be fixed quickly."
For its part Aegon will take no immediate action to replace Mr Denning, the company confirmed.
In a statement released this morning, Aegon said its next step in light of Mr Denning’s departure was to assess the kind of skills it needs in this area.
The firm stated: "We’re currently assessing the capabilities we need to drive the business forward."
Bella Caridade-Ferreira, partner in consultancy firm Fundscape, did not think Mr Denning's departure would have a "major impact" on the replatforming as most of the work was already done.
She said: "Richard Denning is an excellent COO whose expertise lies in managing and implement complex projects. His work at Aegon is done and it’s time for him to move on."
The Aegon platform business has been plagued with problems since May, when it sought to migrate 400,000 Cofunds users to the inhouse platform in an attempt to phase out the Cofunds brand.
Since then advisers have reported a range of problems, and one described the service level agreements, which are a guide as to how long various tasks should take to fix, as a "joke".
To deal with the problems, which included long telephone waiting times and struggles to transfer assets off the platform, the company moved 200 staff from other parts of the business to the platform.
In an update this month it said some of the major servicing issues have now been fixed but clients may still be facing some disruption.
Mark Locke, communications director at consultancy firm the Lang Cat, said: "Replatforming exercises are immensely complex and challenging projects to plan, deliver and execute.
"Any provider involved needs to recognise this, and needs to ensure the corporate focus is unwavering. If things go wrong it is never down to one individual, it’s because the business as a whole underestimated the complexity of the project, and failed to manage the risks accordingly."
Aegon has said it has been in regular talks with the FCA since this saga began, but that it has not been part of a formal regulatory process.