Clickbaiters are worse than Putin. Disgusting creatures.
Saving you a click:
SpaceX believes that vibrations caused a failure of a fuel line in the aft section of the upper stage (i.e., Starship, not its Super Heavy booster), leading to a fuel leak.
I was hoping the answer was "because musk wasn't inside" and the next one he needed to be in, but sure, it's built like a cyber truck is pretty embarrassing also
But also, fuel leaks are really common with rockets, and we know how to prevent them from happening. The fuels rockets use can escape through the tiniest of faults, and the complex fuel systems they use have numerous potential points of failure. As such, it is standard practice to find these potential leaks with intensive pre-flight checks to identify and solve these issues before they escalate into a catastrophe.
It's pretty standard practice apparently, it IS embarrassing.