It's a joke, not about an actual tragedy. A good reason to put a glass of water on bedside table is because you might be thirsty in the middle of the night. Yo

It's a joke, not about an actual tragedy. A good reason to put a glass of water on bedside table is because you might be thirsty in the middle of the night. You might accidentally knock the glass over and cause a huge spill instead. So "in case he causes an accident" is silly. If in real life someone knocked over a glass of water that they put on their bedside table, it's just like the joke, and "tragic". (And an example of life imitating art).