"We have our problems and we haven't offered the students proper teaching," he said.
"Passing was too easy. One unit started students who were supposed not to pass and there are some lecturers who let them pass, and the school from the management level hasn't found this issue.
"We haven't supervised our team well, so it's our school's mistake."
He said the college's three other departments were all headed by people with doctoral degrees and included teachers with NZ experience.
"Our engineering department, we have got seven PhDs from Auckland University and AUT, so they have NZ experience, they were already teaching students at Auckland University, so they bring the Auckland University and AUT level to ICA so we have no problem," he said.
"In business and management some have NZ experience, some don't, so that means they had a mixture. Some low- or no-NZ-experience staff, they have made a mistake, but we had to find it. We haven't given the right staff training for them. That's why I totally agree with their decision."
He said he would like to introduce business and management courses again, but not next year.
"Next year is too fast. We need to do things properly," he said.
"For us, it's a good experience. We would like to improve ourselves, but slowly."
NZQA deputy chief executive Dr Grant Klinkum said NZQA would "be assisting the International College of Auckland to transfer around 80 international students to a high-quality tertiary provider, after a voluntary withdrawal of accreditation by ICA".
The accreditation relates to four programmes offered by ICA: NZIM Diploma in Management (Level 5), NZIM Diploma in Management (Advanced) (Level 6), National Diploma in Business (Level 5) and New Zealand Diploma in Business (Level 6).
"Routine monitoring by NZQA identified quality assurance issues in relation to ICA's assessment and moderation of these programmes," Klinkum said.
"As a result of these issues, ICA has opted to undertake a voluntary withdrawal of its accreditation of these courses with the assistance of NZQA.
"NZQA, ICA and the new provider have ensured students are fully informed and are working together to provide a transition package that allows these students to continue their studies with a full package of learning and support."
As well as its two Auckland locations, the college website lists an address in Garden Place, Hamilton. But Zhu said that was a new site, for information technology only, with the first students due to start there next February.
In the past year NZQA has cancelled the registration of five tertiary education organisations including four that enrolled international students.
