Alex Ferguson has revealed that loyalty to his wife, Cathy, was the key factor in his decision to retire from football management at the end of the current season.
The 71-year-old Scot enjoyed an emotion-charged farewell in Manchester United's 2-1 victory over Swansea City at Old Trafford on Sunday, his last home game after more than 26 years in charge of the new English champions.
The fixture came just four days after Ferguson's announcement that he is to retire stunned the football world and, after the celebrations that followed the victory, he took time to explain the reasons behind his decision for the first time.
"Around last Christmas," said Ferguson, when asked when he had decided to bring an end to his reign.
"Basically, things changed when Cathy's sister died. She is isolated a lot now and I think a lot of the time, for 47 years, she has been the leader of the family, looked after our three sons and sacrificed herself for me.
"Now she has the grandchildren, and they all dote on her, but now she has lost her best friend - her sister - so that was important.
"I think it is also important to go out as a winner. That is really important at this club. It is all I ever wanted to do here - be a winner."
Ferguson and United had hoped to delay the announcement until later in the build-up to the Swansea game, only for rumours to run rife through Manchester on Tuesday following a club golf day.
"It was very difficult to keep it a secret," added Ferguson. "There were some times when we almost blurted it out to the family.
"We told our sons in March, but my brother didn't know until Tuesday night. I wanted to tell the players first really, the players and the staff.
"But unfortunately, there were rumours going around on Tuesday. So all that started to speed it up a bit."
Fittingly, given United's track record of scoring dramatic late goals on Ferguson's watch, United beat Swansea with an 87th-minute winner from Rio Ferdinand after Swansea's Michu had cancelled out Javier Hernandez's opening goal.
Ferguson confessed that such late drama is the one aspect of football management he will most miss.
"The last-minute goals. I love them," he smiled. "We lost a few, but it's part of the history as well.
"It is hard to look back. I have never done that, but I have plenty of time to do that now. The most important achievement, without doubt, was winning the first league (in 1993). Once we did that, a door opened.
"We just grew and grew after that and saw some fantastic changes. There have been some great players and it has been an honour to manage them; different personalities and different cultures. It has been a fantastic challenge of management."
Ferguson, who delivered a post-match speech on the pitch before United were presented with the Premier League trophy, confessed that the occasion almost got the better of him.
"The atmosphere today was absolutely magnificent," he said. "It was fun, there was enjoyment and it is great to be in the stadium where everyone is enjoying themselves.
"I didn't know what to say. I was grasping at things that I could possibly say. I spoke to my son Jason in the morning and he said, 'Go with the flow, start talking, and you'll get there.'
"I babbled on a bit, I suppose. It was emotional. During the week was emotional with the staff. That was hard. They'll get through it."
While Ferguson also used his platform to appeal to supporters to back his successor, David Moyes, when he takes over from him in July, the veteran's own future looks no less busy.
"I have a lot of things to do, a lot of projects," he said. "My son, Jason, has been organising a few things, my ambassadorial role at the club and a directorship, so I won't be sitting still, believe me.
"My French is not so bad, my piano playing is not very good, so I may have to get a tutor if I have the time."