Shredding of “Girl with Balloon”

This is a video showing a painting being shredded after selling at an auction for more than $1.3 million. During all the trial runs, the painting was completely shredded by the printer but at the auction the painting was only half shredded. I am extremely shocked that anyone could do this, as the painting costs an insane amount of money.

A friend showed this to me recently and it completely blew me away. Why would anyone do this?!?

Source: https://www.thefader.com/2018/10/18/banksy-video-shredded-painting