While Starship took to the skies on its maiden flight, the slow build of power started to devastate the launch pad (or Stage Zero as SpaceX refers to it) and surrounding area with debris. Though currently unconfirmed, debris may have struck the bottom of the Super Heavy Booster, causing it to lose engines right at liftoff.
This suggests that the anomalous behaviour was visible even before the ship lifted off. Wouldn't this sort of thing be grounds for a shut down and scrub?
Was it because it happened so quickly, or because they saw no benefit in delaying the launch (i.e. the damage is already done, why not make the best of it)?