Roos said on Tuesday while the Demons were never found guilty of tanking in the 2009 season to secure a priority draft pick, it was obvious that was what happened.
An AFL investigation found the club didn't set out to deliberately lose matches, but the Demons were fined while then-coach Dean Bailey and general manager of football operations Chris Connolly were both found to have "acted in a manner prejudicial to the interests of the AFL".
Roos said the losing habits were hard to shake.
"Tanking has put the club where it is," he told reporters.
"If we want to be in the same position in eight years, then I will tank because we're seven years down the path and we have not recovered as a club from that era."
Roos, who was Sydney Swans coach at the time, said he didn't blame the Demons because the incentive of priority draft picks was there.
But he believed many of the players from that era still at the club were feeling the impact and it wasn't worth the risk teaching your team to lose.
"The carrot was there and we all know that teams were playing for ladder positions in reverse order," he said.
"Half of the footy world thought it was good management, including myself, but having taken over the club now that was involved in it, I can look back now and say it won't happen again."
He felt that AFL clubs in general had learnt from the Demons, and teams out of finals contention now looked at the last matches of the season as a pre-season for the following year.
"Teams really want to set good habits and want for their young guys to come in and play well, so I think this year you're going to have a really fierce competition to the end, which is terrific."
While his team has only managed four wins and face ladder leaders Hawthorn on Saturday at the MCG Roos, said the Demons had improved dramatically.
He said they needed to build confidence and self-belief that they could close out matches.
