O'Leary was not the most popular boss with Villa fans, but is adamant that he was a success at the club.
O'Leary was appointed as Villa boss in 2003 and made a great start to life in Birmingham, leading them to finish sixth in the Premier League in his first season, a placing which at the time was their highest in four years.
However, things soon went backwards as his side finished 10th the following season and narrowly avoided relegation in 16th in his third campaign.
The latter period of his time in charge was marred by a widening gap between himself and supporters, most notoriously summed up by the famous "We're not fickle. We just don't like you" banner hung in the Holte End in 2006 after the manager had accused fans of a lack of support.
Given what followed O'Leary's sacking in 2006 - Randy Lerner bought the club from Doug Ellis and appointed Martin O'Neill shortly afterwards, a transition which would yield three consecutive sixth-placed finishes - many fans have dismised O'Leary's reign with hindsight.
In fact, some would likely argue that the former Leeds manager's biggest success was the bargain signing of future club captain and fan favourite Martin Laursen.
However, in a candid interview with the Telegraph, O'Leary has insisted that he did well at Villa Park, arguing that he would not have lasted as long as he did if he was not doing a good job.
O'Leary said: "I know I did a good job at Aston Villa. At Villa, I was much more the manager but Doug Ellis was selling the club.
"Doug is a shrewd man and, like if you are selling your house, you make it presentable but you are not going to spend a lot of money on new carpets or windows.
"I wouldn’t have lasted more than three years if I was doing a bad job."
The 58-year-old has not worked in a coaching role in the UK since leaving Villa a decade ago, most recently serving as manager of UAE side Al-Ahli in 2010-11.