Here's a photo I took in London. The Tunnel Vision concept came to me when I thought of a tunnel as a "box" and how there's a popular metaphor "think outside the box" but no one one really says "know what's inside the box, then think outside of it" and as a result people relate to the concept by thinking outside of the box without even knowing what's inside.
At the end of the "tunnel" on the other side is the "outside of the box" and you would have experienced what's inside by passing through the tunnel and would now know why you should or should not think outside of it.
