When you first learn to play chess they tell you to get the King safe. It's one of the mantras of the opening. Develop your pieces, get them to active squares, ready to attack.
Every piece except the King. The King must be tucked away in the corner behind as much cover as possible. Wrapped up in cotton wool. Makes him seem weak and frail doesn't it?
Well the King is not so weak and frail. He is actually stronger than a minor piece. A lone Rook is also well advised to keep a respectful distance.
No the King is simply more valuable that's all. All good players watch out for that point in the blurry lines between the middlegame and the endgame. The moment when the King must stride towards the center and become the central player in the fight.