New Delhi, Jan 30 (ANI): Oprah Winfrey, who celebrated her 60th birthday on Jan. 29, believes that seeing the best in even the worst people has been her greatest achievement in life.The talk show queen wrote in an open letter in The Oprah magazine that never shutting her heart down is the best thing she has ever done.The ' Butler' actress asserted that even in her darkest moments, she remained faithful, hopeful and open to seeing the best in people, regardless of whether they were showing her their worst.