So you don't think a judge can think someone is guilty and be objective enough to make a ruling based solely on the evidence and arguments of the attorneys? Seems like you have little faith in the justice department.
No, I don't and neither should you, that is why there is constitutional power to remove a judge. The task is to decide what it means for a judge to misbehave. To say that a judge is misbehaving is to judge that his or her act or omission falls short of what we rightfully expect from judges.
A judge who swears to tell the truth and then misleads the court is clearly unfit to remain in office. Likewise a HC who swears to let the competition and performance decide the starter and then mislead current players by declaring that he hopes a future player wins the job is clearly unfit to be a judge.
Judges must be held to higher standards because they hold the unique position of administering justice. Judges must do justice and give people reason to believe that justice is being done. Judicial misbehavior that justifies removal from office has a critical quality. It stains the judge's character and saps public confidence in him or her and in those who administer justice. And so the judge is unfit for office.