Images are showing click mechanism. On image A is mechanism with pin (as wesuggested) and on image B is mechanism with ball from your samples. When shower hook spins (red arrows) there is a force onpin (red line) or ball (red dot). Because contact surface on ball mechanism is much smaller than at pin mechanism, also pressure is much higher at same force. Therefore material can deform (yellow arrow on image D) and ball can slide out of its slot (image C), which blocks spinning os shower hook as it has happen on one of your sample. We strongly suggest to use pin instead of ball.