The former contestants on Simon Cowell's talent show star in the new clip, documenting how it launched their careers.
Olly Murs says: "Every time I went out there on a Saturday night I thought 'God this is the best job ever.'"
And Leona Lewis tells how the show was a "big learning experience" for her, while One Direction say they felt like "the five luckiest guys on the planet".
The X Factor is due to return in the autumn, once again with a new judging panel. Kelly Rowland has parted ways with the show, so former Pussycat Doll Nicole Scherzinger will take her place alongside Gary Barlow, Tulisa and Louis Walsh.
It has been reported Barlow, who was recently made an OBE in this year's Queen's Birthday Honours List, will mentor the Over- 25s group on this year's show.
The Sun claims he has been given the job of trying to create the first winner from the Overs category since Steve Brookstein won the first series in 2004.