Or a third option - a faulty part/installation that doesn't say anything about the design or maintenance.
The larger the ship, the more complex and more opportunities for something to go wrong. Charles de Gualle took over a decade to commission and had a broken prop during sea trials. I think it was Admiral Kuznetsov had problems in that the water kept freezing that meant blocked toilets for half the crew. Varyag/Liaoning went into drydock in 2005 and was "commissioned" in 2012, but officially classed as a training ship until a few years ago. We've got no idea what might have gone wrong in those years.