Rock legend Peter Maffay (73) struggles with being graded. "I've hated exams in my life. If someone came to me and said I'd get a grade of 5, I said: "What right does anyone have to judge that,"" Maffay told the German Press Agency. "There are many criteria that are crucial and may not even be gradeable."

The musician can be seen as a coach in the twelfth season of the casting show "The Voice of Germany". In the final this Friday (8:15 p.m., Sat.1), the television audience will decide who wins the show.

"I wasn't necessarily a friend of such formats because in the past the talents were dealt with in a way that I don't think is right," admits Maffay. "I made the mistake of lumping everything together and of course I got inked on The Voice." Things are different there, his balance sheet is positive.

The Voice