The Manchester United manager has been in charge at Old Trafford for 25 years, and when asked in an interview with The New York Times if anyone would repeat that feat, Ferguson said: "I don't think so. I'm a phenomenon."
He continued: "I have certainly mellowed. There's no question about that. It's a more fragile human being that I am dealing with today than 25 years ago.
"They are cocooned by modern ideas, modern parents, modern agents, and they are cocooned by their own image at times.
"It's a different world for me, so I have to change myself to adapt to that. I have changed because of these things.
"One thing I've learned in the last decade is delegation. In the early days, I was involved with scouting, coaching, youth everything. You can't do that for a long period of time."
Ferguson went on to lay down the law about who the top dog at Old Trafford was: "You have to remember that the most important person at Manchester United is the manager.
"The minute a footballer becomes more important than the manager, your club is dead. The history of the club goes down the drain. I am the most important man at Manchester United. It has to be that way."
Of the Glazers, he said: "I have had a great relationship with our owners. They never bother me. They never ask questions, they never phone me and they never interfere with my job. I am in a privileged position."
And when asked if there was a time when he would 'burn out and leave', Ferguson said: "I'll give everyone a tip here: retirement is for young people, not older people. Young people can do something else. When you're older and you've been on that treadmill for length of time I have been on it, if I get off that treadmill, where do you think I am going? Down there. Trust me. Retirement is for young people. When you get older, don't retire."