Every person is a new door to a different world.
A door can be opened and closed, locked or broken. A door can be old and rusted or new and unscathed. It can be repainted and decorated. Parts can be replaced. It can be large or small, with a doorknob or not. It can be automatic or have to be opened manually.
It can lead to a home, stairs, a hospital, a place of worship, an elevator, an airplane, a closet, a secret, or somewhere not held captive by walls. A door can lead anywhere. A door can lead you into the world of the mind of anyone. Wherever a door leads, it leads to a different world. It leads to something different. Like a fingerprint, every door is unique. No two doors can lead to the same perspective.
Just because a door may not be made of gold does not mean that it cannot appear golden and contain a priceless treasure behind it.