"It's not making financial sense any more and they had to do something about it. Hard decisions had to be made," he said.
"It's hard to pinpoint [what went wrong] because we weren't involved in all that decision making but I think obviously the manufacturing side of things was going to come unstuck at some stage."
Manufacturing and designing cars in Australia was costly, he said.
Mistakes were made along the way around messaging and marketing of the product, he said.
"I think a lot of people still thought Holden was going to disappear when the factory closed. The story might not have been told as good as it could at the time.
There was also an issue keeping the product range up to date and providing cars that people still wanted.
Numbers had dwindled massively in Oz down to 4% market share whereas NZ was at around 8.5 per cent at last count.
"Australia being the much bigger market they needed to be doing a lot better than what they were."
