What happened with the truck window on stage?

“Oh my f---ing god. Eh, not bad. Room for improvement. We threw wrenches, we threw everything even literally the kitchen sink at the glass and it didn’t break. For some weird reason, it broke now. I don’t know why. We will fix it in post. Yup. Sledgehammer impact on door cracked base of glass, which is why steel ball didn’t bounce off. Should have done steel ball on window, *then* sledgehammer the door. Next time …”

— Elon Musk, 21 November 2019 · Post on X ↗