The Dutchman has said that he initially intended to retire at the age of 55, but nearly nine years later he is still doing the job he loves.
Van Gaal will be 66 in August 2017 and insisted that he has already promised his wife that he will not to go back on his word of retiring when his contract with United comes to an end. Even if a Qatari club offers him a big payday, Van Gaal insists that he will not be tempted to extend his career.
"I will give it up [in 2017]," he told reporters. "I promised that to my wife. We have not many years together any more. That is the reason.
"I have to admit I have said to her, when I met her and after our relationship seemed to be very good, that at 55 I shall quit. I am still working and next week I am 64.
"Do I have to go to Qatar to earn still more money? I don't think so. You have to enjoy also your life and your relationship with your wife."
The 63-year-old is eager to add a Premier League title to his collection of accolades which include league titles with Ajax, Barcelona, Bayern Munich and AZ Alkmaar. He has also guided Ajax to Champions League glory and last year helped the Netherlands finish third in the World Cup.
"I have done everything in my career as a manager," Van Gaal added. "I have been in the Netherlands, my home country, in Spain, which is a fantastic league, and Germany is also a fantastic league.
"I participated in the World Cup. The only wish was the Premier League. Now I am here."
However, Van Gaal admitted that winning the Premier League will be a lot easier said than done as United will face stiff competition from the likes of Chelsea, Manchester City, Arsenal and Liverpool.
"I want to do that in [my] three years [at the club]," he said. "If it is this year, then I am very happy, but I cannot say this year we shall be the champions.
"We have to fight for it. That is the most important thing. Until the end we have to challenge for the number one, and maybe we are.
"The long-term vision is to win the championship or an FA Cup or a Champions League."