Twenty ring ties into a listed brick faced building wouldn't stop a truck pulling it off the face of the building though would they? It does look like there were a lot of joints in the pavement lift so once the ties just above that have pulled out and the scaffold has lifted off the joint pins, the scaffold is going to have little or no support from the ground and is only going one way. It is difficult to see what protection was there to keep vehicles and scaffold apart, the lack of which was probably the worst error. (On a day like today, I probably wouldn't bother with a hard hat if there was nothing left above 6' to fall on my head!)