The former Borussia Dortmund star completed his switch to the Gunners during the January window, as part of a deal that saw Alexis Sanchez move in the opposite direction to Old Trafford.
Now enjoying his time with the Gunners, midfielder Mkhitaryan feels his switch to north London came at just the right time in his career.
"Of course sometimes you need some refreshing," he told ESPN Brasil.
"And I think this was the best moment for me, because there were a few things that didn't work out in Manchester.
"I was 29 years old, I wanted to play more, because I know that in a few years' time I'll be able to end my football career, and it's very important for me to make my name bigger.
"That's why, maybe, it was the best moment, and the best time to change something and to get a new challenge, a new club, and start everything from zero."