Keane has been out of work since departing as Sunderland manager last December, but maintained the challenge and timing of taking over at the Suffolk club was right for his return to the game.
His former United team-mates Bryan Robson, Mark Hughes, Steve Bruce and Paul Ince have experienced varied success in their own management careers, but Keane wasted no time putting the record straight.
"Who are the good managers you are talking about?" he asked.
"Sparky [Hughes] and Brucey have not won a trophy have they?
"They have potential. Steve Bruce has had a good season, but Steve Bruce has been manager how many years?
"Sparky has done a brilliant job at Blackburn, but is facing different challenges at Manchester City.
"We are all facing different challenges.
"Until an ex team-mate of mine from 1994 goes on and really achieves something, then I would not agree with what you are saying about being a successful manager.
"You need a bit more than some of those managers have achieved yet."
Keane added: "With me, it is a desire to win, a fear of losing, wanting to achieve something in my life.
"I had five months out of the game, and while I really enjoyed it, I had this gut feeling that it was time to try something.
"I believe I can potentially be a good football manager.
"I have done nothing in the game yet, I did okay at Sunderland, but I want to do better than okay."
Meanwhile Keane has vowed to write a new chapter in Ipswich's history as he bids to get them back into the Premier League.
The Suffolk club were champions of England under Sir Alf Ramsey in 1961-62, while twice finishing runners-up at the start of the 1980s with Sir Bobby Robson at the helm after an FA Cup win in 1978 and the UEFA Cup triumph in 1981.
However, much water has passed under the bridge since then and Keane is determined to focus on the future.
"There are lots of clubs in the championship who feel they belong in the Premiership - Nottingham Forest, Leeds, Sheffield United; look at Charlton now," said Keane, who took Sunderland up in his first season in charge.
"Ipswich are a club with a good heritage, who did well in the 70s and 80s.
"As much as it is a massive part of the club, it is about now and what I achieve.
"I am looking forward to it."
Bryan Klug has placed in charge of the first team for Saturday's game at Cardiff while Keane acquaints himself with his new surroundings.
"I am very open minded," said the new Town boss.
"There are a lot of injured players and a lot of players out of contract.
"It will be a busy few months coming up.
"I will probably be bringing in one or two players, but not over the next few weeks."
Keane added: "Funds have been mentioned. We will take stock over the next six weeks.
"It might suit me that a lot of players' contracts are up.
"I am convinced the players will enjoy working with me. I have simple demands - be on time for training and give 100%, then you will be fine.
"If they do not, it will be a very brief relationship.
"I have no problem people making mistakes, as long as they keep going day in, day out."