De Laet joined Leicester this week.
"Ferguson wanted me to stay next season. He said do preseason, then we would see if I was to stay or would be loaned. But when Leicester made an approach, I did not hesitate.
"Whether there was interest from other clubs? My manager had several calls from interested clubs, but Leicester were quickest."
De Laet added: "It's been nice at United. I have had enough time to show my ability, but I failed. Pity.
"I can say that I've trained with the best players in the world. But if you do not play, you can't say you did much."