Whilst having a person on constant standby to point travellers in the right way might be fail proof, it would be unsustainable. Instead we can replace the person with a sign, a sign with arms and perhaps even hands with pointing fingers.
Show me the right path, O LORD; point out the road for me to follow. Psalm 25:4
Jesus answered, “I am the way and the truth and the life.” John 14:6a