The Portugal international was strongly linked with a move away from United this summer.
But the winger ended speculation over his future by signing a new five-year contract with United last week.
"I am very content with my new deal at Manchester United," Nani told the Daily Mirror.
"This summer was not easy but after a lot of thought and talking to David Moyes I believe it was the best solution.
"I feel I can offer many things to United. I had other important offers but without a sufficent challenge to make me want to leave United.
"The coach would not guarantee me a place in the XI more than any other player. I know I must work hard to get into this team.
"That is my objective for this season."