External safety auditor David Randall from DRA Safety Specialists conducted his first safety audit of the park in 2013, years before four thrill seekers died on a ride in October 2016.
He has told an inquest into the deaths that Dreamworld had a culture of being "family oriented and family based" but there had been pushback from staff when he tried to change operational procedures.
"It was hard to overcome. Many of the people had been there for 25 years with their ways. It was a cultural thing that we had to move forward," Mr Randall said on Thursday.
"The management was good, very very good, but there was resistance to change in the workforce because this is not what they had done for the last 20 years."
Mr Randall said staff were required to perform a check list for ride safety, but many did not follow the criteria.
"They would cover off the requirements off the check list, but they all had their own system, I was still finding people doing things their own way."
New Zealander Cindy Low, Kate Goodchild, her brother Luke Dorsett and his partner Roozi Araghi died after a water pump on the Thunder River Rapids ride malfunctioned, resulting in two rafts colliding and flipping.
