Rooney has retured to the England squad to make a farewell appearance in aid of his charity foundation against the USA at Wembley on Thursday. He won the majority of his caps while a Man United player.
"Of course you miss it. It was the highlight of my career, playing for Man United and I was there for so long. But it was the right time," he told 'MUTV'.
"I wasn't playing, first of all. I have always been a player who wants to play. Obviously I spoke to the manager and it didn't look like I was going to play, so it was the right decision and the right time for me to go.
"Obviously, you wish, the ideal situation was staying there and finishing your career there, but football changes. Different things happen and things happen for a reason."