Possess a Fighting Spirit
People tend to shy away from change. We are more comfortable with the status quo. But not facing the challenge of new or difficult things, and being satisfied with the present, means that we are already regressing.
"Challenge" implies establishing a lofty goal, rejecting the status quo, and constantly innovating. While the word "challenge" sounds uplifting, it must be backed by the courage and perseverance to stand up to any difficulty, regardless of the effort required.