The Dutchman arrived at Old Trafford with the aim of returning United to the UEFA Champions League after their seventh-placed finish last season.
United occupy fourth position - and the last qualification berth - with 10 games to go, but the cup offers their only chance of lifting a trophy in Van Gaal's maiden campaign in charge.
"I think a title, you can say you play throughout your profession or you manage throughout your profession but that is not enough," he said.
"You want to win something so the players want to win something, and also the manager and the fans want to win something, so when you win a title like the FA Cup, and in England the FA Cup is very important, that gives you a lot of value.
"When you fight for something and you get it you are pleased. And also for the players, but also for the manager, and that is the second thing which is important.
"With players who already have a high level final that they can win, getting that experience brings players further."
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