Daniel Radcliffe, who played the titular character in all the Harry Potter films, worried at the end of his work on the successful franchise that he wouldn't be good enough to tackle other roles.
The 23-year-old actor also said that he hated having time off as his concerns escalated.
"With any kind of artistic thing it's a muscle, like any athlete, and the moment you're not doing it, you lose all confidence," Contactmusic quoted him as telling The Independent Radar magazine.
"That's why I'm terrible with down time. And actually what's been great about the last year and a half is that I have found a confidence.
"Before, basically, by the time we got to the end of 'Potter', I was going, 'I don't know if I can do this, I don't know if I'm good enough'," he said. (ANI)