I’ll tell you, your clothes get wet and, in many cases, ruined!
A friend of mine was headed back home. When she, and many other passengers, went to the baggage claim to get their bags, they discovered their luggage was soaked….and smelled really clean.
What had happened was, another passenger had packed some sort of liquid cleaner in their luggage (why???????), and, in flight, it had opened and spilled all over everyone elses luggage.
How to prevent this from happening to you?? A few options: never fly again, or, my personal choice, make use of an ingenious item that costs only pennies.
The large black trash bag. Now, when I travel, I open my luggage to be checked, place my black trashbag inside, open, THEN put my clothes inside that bag. I close the bag, then close my luggage. This way, even if some dimwit does pack liquid cleaners in their luggage, my clothes are safe.