Let's say you buy a spare battery for your laptop and forget to put it in your carry-on (as per IATA rules). What happens next? Some possible scenarios:
- The airlines tend to ignore that regulation and don't bother checking for batteries
- The airline will open your bag, take out the battery, and leave a 'sorry' note
- The airline will pull you off the flight and force you to take out the battery
The question is inspired by a real-life scenario where I've remembered about the batteries regulation a few seconds before checking in my luggage.