“Sledgehammer impact on door cracked the base of the glass, which is why the steel ball didn’t bounce off,” he wrote.
“Should have done steel ball on window, then sledgehammer the door. Next time.”
Over the weekend, Mr Musk tweeted footage of an earlier demonstration, carried out behind the scenes moments before the launch, showing the windows withstanding the impact of the steel ball.
Despite the awkward mishap, Tesla announced it had received more than 200,000 orders for its Cybertruck following the demonstration.
The success of the launch event has caused some speculation on social media the incident, viewed millions of times online, had been orchestrated to go viral.
“It’s hard to say if that one infamous moment is why Tesla has been able to get 200,000 deposits on the Cybertruck but all the extra attention certainly didn’t hurt,” said Jessica Caldwell, from vehicle marketplace Edmunds.
“Moments like that are why Tesla has such a passionate fan base: while most executives are always hyper-rehearsed and polished, Elon Musk has never been afraid to show his human side, for better or worse.
“Tesla’s fans are notorious for giving the company the benefit of the doubt and assume the technology will be sorted out by the time the truck actually goes on sale.”